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Premium Member
8,052 Posts
Discussion Starter #2

Many users on the internet only care about a couple things, "Can I get to my e-mail?", "It works so thats all that matters!", "Look at the cute cuddly LOLCats.". Well, do you know what comprises the internet and how each mechanism works? What if something went down, would you know how to respond to a situation like this? Say that you have your Internet Line go down, however your modem still responds to pings, the noise to signal ratio is looking good, and your ISP blames it on you not powercycling your modem. Would you know how to respond? I want to give you the knowledge to better understand the aspects of how the Internet works, and the hardware used in the Internet system. What will be covered is the hardware, makeup, and construction of LANs, WANs, and software devoted to networking.

Premium Member
8,052 Posts
Discussion Starter #3

Lets go through some of the basics. Everyone has some type of modem in their house. Whether it be for the internet, telephone line, TV, or any other device that uses a modulated line. A modem is exactly this. A Modulating/De-Modulating mechanism. The function of the modem is to encode a signal so that it can be carried over a form of media from point A to point B and be easily decoded on the other end. Mostly anything that is brought to you by data from the internet is directly transferred through a modem at some point. Originally, the modem started out as a 300 bit/ps piece of hardware looking like this:

Credit to: Jason "Textfiles" Scott for uploading the picture.

This piece of hardware is basically an acoustic coupler, picking up the fluctuations and tones of the signal. What usually would happen would there would be two modems, similar to that of a client and server, however these modems would be called the Originate modem and the other called an Answer modem. However, though you may be thinking that the Originate modem would be the computer, and the the Answer Modem would be the server it is in reality the opposite. The computer was always the answer modem, and the dumb terminal was the Originate modem. These modems would connect to that dumb terminal to gain access to the web, however these days, the modem connects to the Internet Service Provider (ISP) and the ISP connects us to the internet. How this operates is that we have a Point-to-Point Protocol (PPP). Once the information (packet) has been transferred to the modem, it is then transferred to the ISP and to the server. The same steps are required to get the data from the Server back to your computer. There are different types of connections and classifications for modems.

  • Cable
  • Phone-Line
  • Cellular
  • Fiber-Optic

And future implementations of networking technology will most likely also have modems.

To understand how a cable modem works, you need to understand a bit about electricity. A signal operates over an electrical field. In the instance of cable or co-axial connections, the data being sent to the modem and TV receiver are able to be put into the same electrical range. Electrical Range is commonly referred to as Bandwidth. Bandwidth is measurable in Hertz, since the transfer rate is measured in Hertz. The only ways to increase and boost transmission range is to increase the amount of lines or increase the speed on the lines. Due to the standards of coaxial cables, these cables can carry several hundreds of megahertz on a given line. However, bit rate is not solely dependent on frequency.

A Digital Subscriber Line (DSL) modem works on a Plain Old Telephone Service (POTS) infrastructure. This infrastructure is basically using the telephone lines that are already in place for day to day internet services. The modem at the customer premise communicates through provider equipment known as the DSLAM (Digital Subscriber Line Access Multiplexer). The modem negotiates a bandwidth value with the remote end based on cabling conditions. The service generally supports speeds ranging from ~1 to 25 Mbps depending on the standard used. A downfall to DSL, however, is that the signal loses its strength the longer it travels from the provider's office to your equipment. This rating is measured and negotiated between points with values known as "Attenuation" (Signal Loss).

A phone-line modem is what several used in the 90's, and still use today either because cable, DSL, or fiber is not in the area, or as a backup for businesses when their own internet system goes down. One of the earliest forms of Internet Connectivity. Since recent forms of dial-up modems max out their transfer rate at 56kpbs, ISP's have come up with server side compression. This allows images, text, and other media on the requested media to be compressed to allow a higher rate of transfer. How this system works is similar to the older methods of modems. It uses a Line-to-Line connection to initiate and connect to the ISP's hub.

Cellular modems are becoming increasingly widespread as faster and longer range technologies are being developed and implemented. They are a cost effective solution for generally lower-bandwidth demands and convenience as there is no additional cabling required to reach the remote end. Cellular modems come in a variety of formats including laptop 'air cards', router modules and even as an integrated component in cell phones.

Fiber-Optic 'Modems' can also generally be referred to as 'Media Converters'. Their main function is to convert the beams of light received through the fiber into another transport medium such as copper RJ-45, which exist in most computers and networking equipment today.

Premium Member
8,052 Posts
Discussion Starter #4
Networking Infrastructure

You may be wondering what is included in my field for the Networking Infrastructure. Well, every home network is made up of a combination of the following:
Note: All layers mentioned here are in terms of the OSI Model unless otherwise noted

  • Hub/Repeater
    A Hub or Repeater operates on Layer 1 of the OSI Model (Physical). It is a "dumb" device since the only objective it has is to transfer bits between one interface to the next interface. The device forwards all bits received toward all of its other ports. It does not think for itself, so a packet "collision" is possible when two packets are sent at the same time to any port.
  • Switch
    Most switches operate on Layer 2 of the OSI Model (Data Link). It is considered a smarter device than a hub due to the fact that it uses a Media Access Control (MAC) address table to correlate frames to specific interfaces. The role of switch is to expand connectivity to multiple devices in a network. In most households we use Layer 2 Switches, which are responsible for memorizing the MAC address table and what port/interface is associated with that entry. Switches, however, can operate on multiple layers of the OSI model. A switch with layer 3 capabilities can take up some of the functions of a router below for routing packets between different networks or subnets.
  • Router
    A Router operates on Layer 3 of the OSI Model (Network). There are many different types of routers though they function at a similar fundamental level. The primary functions of a router are to transfer packets between different networks, negotiate routing protocols with other routers and manage routes. These protocols and routes allow the router to know about where to forward packets so they can reach their intended destination. Many home routers receive a default route from the ISP to forward all traffic to the ISPs router specifically. From there, the ISP router maintains a full table of routes on the Internet in order to have your traffic reach its destination. The Internet as a whole is mostly comprised of routers. Usually much more powerful, comprising of several different types of connections including serial, phone lines, Ethernet, fiber-optic or coaxial cables.
  • Wireless Access Points (WAP)
    These can either be extensions of a current wireless network or allow for a wireless network to be created from a wired only topology. These devices operate on the IEEE 802.11 standards, which is the underlying creation of "Wi-Fi". These operate on Radio Waves in a means of communications. These are broken down to two different classifications. Wireless Frequency in Megahertz, and Wireless Channel. The listing is below

ChannelFrequency (MHz)

  • Networking Interface Cards (NIC)
    Networking interface cards are what essentially connects your home network together with wires. These NICs can be used in any type of connection field (IE: Ethernet, Fiber-Optic, etc). Usually, most home and residential NICs only contain a RJ-45 (networking) jack connection.
  • Wireless Network Interface Cards (WNIC)
    Wireless network cards are the wireless equivalents of their NIC brothers. However, these cards operate on wireless radio frequencies. They offer varying inter-operable standards for connectivity among a variety of frequency ranges depending on the card (2.4/5 GHz).

Premium Member
8,052 Posts
Discussion Starter #5
Internet Addressing

At a residential connection, to interact and communicate with anyone you will need an Internet Protocol Address (IP Address). Each country and region are leased a certain range of numbers which are given to the Regional Internet Registry. The Regional Internet Registry is then responsible for handing out these lease ranges to Local Internet Registries or the National Service Registries, which then hand them out to Internet Service Providers, and then the ISP leases them to the consumer. This forms a hierarchical pyramid, always leading back up the IANA.

A full log of how the IP Prefixes are set up are listed here in plain text or here in XML format. They are copied here and put in a code tag below:


Prefix                  Designation                    Date         Whois       Status [1]    Note
   000/8  IANA - Local Identification                    1981-09                    RESERVED     [2]
   001/8  IANA                                                                     UNALLOCATED
   002/8  RIPE NCC                                       2009-09  whois.ripe.net    ALLOCATED
   003/8  General Electric Company                       1994-05                     LEGACY
   004/8  Level 3 Communications, Inc.                   1992-12                     LEGACY
   005/8  IANA                                                                     UNALLOCATED
   006/8  Army Information Systems Center                1994-02                     LEGACY
   007/8  Administered by ARIN                           1995-04  whois.arin.net     LEGACY
   008/8  Level 3 Communications, Inc.                   1992-12                     LEGACY
   009/8  IBM                                            1992-08                     LEGACY
   010/8  IANA - Private Use                             1995-06                    RESERVED     [3]
   011/8  DoD Intel Information Systems                  1993-05                     LEGACY
   012/8  AT&T Bell Laboratories                         1995-06                     LEGACY
   013/8  Xerox Corporation                              1991-09                     LEGACY
   014/8  IANA                                                                     UNALLOCATED   [4]
   015/8  Hewlett-Packard Company                        1994-07                     LEGACY
   016/8  Digital Equipment Corporation                  1994-11                     LEGACY
   017/8  Apple Computer Inc.                            1992-07                     LEGACY
   018/8  MIT                                            1994-01                     LEGACY
   019/8  Ford Motor Company                             1995-05                     LEGACY
   020/8  Computer Sciences Corporation                  1994-10                     LEGACY
   021/8  DDN-RVN                                        1991-07                     LEGACY
   022/8  Defense Information Systems Agency             1993-05                     LEGACY
   023/8  IANA                                                                     UNALLOCATED
   024/8  ARIN                                           2001-05  whois.arin.net    ALLOCATED
   025/8  UK Ministry of Defence                         1995-01  whois.ripe.net     LEGACY
   026/8  Defense Information Systems Agency             1995-05                     LEGACY
   027/8  IANA                                                                     UNALLOCATED
   028/8  DSI-North                                      1992-07                     LEGACY
   029/8  Defense Information Systems Agency             1991-07                     LEGACY
   030/8  Defense Information Systems Agency             1991-07                     LEGACY
   031/8  IANA                                                                     UNALLOCATED
   032/8  AT&T Global Network Services                   1994-06                     LEGACY
   033/8  DLA Systems Automation Center                  1991-01                     LEGACY
   034/8  Halliburton Company                            1993-03                     LEGACY
   035/8  MERIT Computer Network                         1994-04                     LEGACY
   036/8  IANA                                                                     UNALLOCATED
   037/8  IANA                                                                     UNALLOCATED
   038/8  Performance Systems International              1994-09                     LEGACY
   039/8  IANA                                                                     UNALLOCATED
   040/8  Eli Lily & Company                             1994-06                     LEGACY
   041/8  AfriNIC                                        2005-04 whois.afrinic.net  ALLOCATED
   042/8  IANA                                                                     UNALLOCATED
   043/8  Administered by APNIC                          1991-01                     LEGACY
   044/8  Amateur Radio Digital Communications           1992-07                     LEGACY
   045/8  Interop Show Network                           1995-01                     LEGACY
   046/8  RIPE NCC                                       2009-09  whois.ripe.net    ALLOCATED
   047/8  Bell-Northern Research                         1991-01                     LEGACY
   048/8  Prudential Securities Inc.                     1995-05                     LEGACY
   049/8  IANA                                                                     UNALLOCATED
   050/8  IANA                                                                     UNALLOCATED
   051/8  UK Government Department for Work and Pensions 1994-08  whois.ripe.net     LEGACY
   052/8  E.I. duPont de Nemours and Co., Inc.           1991-12                     LEGACY
   053/8  Cap Debis CCS                                  1993-10                     LEGACY
   054/8  Merck and Co., Inc.                            1992-03                     LEGACY
   055/8  DoD Network Information Center                 1995-04                     LEGACY
   056/8  US Postal Service                              1994-06                     LEGACY
   057/8  SITA                                           1995-05                     LEGACY
   058/8  APNIC                                          2004-04  whois.apnic.net   ALLOCATED
   059/8  APNIC                                          2004-04  whois.apnic.net   ALLOCATED
   060/8  APNIC                                          2003-04  whois.apnic.net   ALLOCATED
   061/8  APNIC                                          1997-04  whois.apnic.net   ALLOCATED
   062/8  RIPE NCC                                       1997-04  whois.ripe.net    ALLOCATED
   063/8  ARIN                                           1997-04  whois.arin.net    ALLOCATED
   064/8  ARIN                                           1999-07  whois.arin.net    ALLOCATED
   065/8  ARIN                                           2000-07  whois.arin.net    ALLOCATED
   066/8  ARIN                                           2000-07  whois.arin.net    ALLOCATED
   067/8  ARIN                                           2001-05  whois.arin.net    ALLOCATED
   068/8  ARIN                                           2001-06  whois.arin.net    ALLOCATED
   069/8  ARIN                                           2002-08  whois.arin.net    ALLOCATED
   070/8  ARIN                                           2004-01  whois.arin.net    ALLOCATED
   071/8  ARIN                                           2004-08  whois.arin.net    ALLOCATED
   072/8  ARIN                                           2004-08  whois.arin.net    ALLOCATED
   073/8  ARIN                                           2005-03  whois.arin.net    ALLOCATED
   074/8  ARIN                                           2005-06  whois.arin.net    ALLOCATED
   075/8  ARIN                                           2005-06  whois.arin.net    ALLOCATED
   076/8  ARIN                                           2005-06  whois.arin.net    ALLOCATED
   077/8  RIPE NCC                                       2006-08  whois.ripe.net    ALLOCATED
   078/8  RIPE NCC                                       2006-08  whois.ripe.net    ALLOCATED
   079/8  RIPE NCC                                       2006-08  whois.ripe.net    ALLOCATED
   080/8  RIPE NCC                                       2001-04  whois.ripe.net    ALLOCATED
   081/8  RIPE NCC                                       2001-04  whois.ripe.net    ALLOCATED
   082/8  RIPE NCC                                       2002-11  whois.ripe.net    ALLOCATED
   083/8  RIPE NCC                                       2003-11  whois.ripe.net    ALLOCATED
   084/8  RIPE NCC                                       2003-11  whois.ripe.net    ALLOCATED
   085/8  RIPE NCC                                       2004-04  whois.ripe.net    ALLOCATED
   086/8  RIPE NCC                                       2004-04  whois.ripe.net    ALLOCATED
   087/8  RIPE NCC                                       2004-04  whois.ripe.net    ALLOCATED
   088/8  RIPE NCC                                       2004-04  whois.ripe.net    ALLOCATED
   089/8  RIPE NCC                                       2005-06  whois.ripe.net    ALLOCATED
   090/8  RIPE NCC                                       2005-06  whois.ripe.net    ALLOCATED
   091/8  RIPE NCC                                       2005-06  whois.ripe.net    ALLOCATED
   092/8  RIPE NCC                                       2007-03  whois.ripe.net    ALLOCATED
   093/8  RIPE NCC                                       2007-03  whois.ripe.net    ALLOCATED
   094/8  RIPE NCC                                       2007-07  whois.ripe.net    ALLOCATED
   095/8  RIPE NCC                                       2007-07  whois.ripe.net    ALLOCATED
   096/8  ARIN                                           2006-10  whois.arin.net    ALLOCATED
   097/8  ARIN                                           2006-10  whois.arin.net    ALLOCATED
   098/8  ARIN                                           2006-10  whois.arin.net    ALLOCATED
   099/8  ARIN                                           2006-10  whois.arin.net    ALLOCATED
   100/8  IANA                                                                     UNALLOCATED
   101/8  IANA                                                                     UNALLOCATED
   102/8  IANA                                                                     UNALLOCATED
   103/8  IANA                                                                     UNALLOCATED
   104/8  IANA                                                                     UNALLOCATED
   105/8  IANA                                                                     UNALLOCATED
   106/8  IANA                                                                     UNALLOCATED
   107/8  IANA                                                                     UNALLOCATED
   108/8  ARIN                                           2008-12  whois.arin.net    ALLOCATED
   109/8  RIPE NCC                                       2009-01  whois.ripe.net    ALLOCATED
   110/8  APNIC                                          2008-11  whois.apnic.net   ALLOCATED
   111/8  APNIC                                          2008-11  whois.apnic.net   ALLOCATED
   112/8  APNIC                                          2008-05  whois.apnic.net   ALLOCATED
   113/8  APNIC                                          2008-05  whois.apnic.net   ALLOCATED
   114/8  APNIC                                          2007-10  whois.apnic.net   ALLOCATED
   115/8  APNIC                                          2007-10  whois.apnic.net   ALLOCATED
   116/8  APNIC                                          2007-01  whois.apnic.net   ALLOCATED
   117/8  APNIC                                          2007-01  whois.apnic.net   ALLOCATED
   118/8  APNIC                                          2007-01  whois.apnic.net   ALLOCATED
   119/8  APNIC                                          2007-01  whois.apnic.net   ALLOCATED
   120/8  APNIC                                          2007-01  whois.apnic.net   ALLOCATED
   121/8  APNIC                                          2006-01  whois.apnic.net   ALLOCATED
   122/8  APNIC                                          2006-01  whois.apnic.net   ALLOCATED
   123/8  APNIC                                          2006-01  whois.apnic.net   ALLOCATED
   124/8  APNIC                                          2005-01  whois.apnic.net   ALLOCATED
   125/8  APNIC                                          2005-01  whois.apnic.net   ALLOCATED
   126/8  APNIC                                          2005-01  whois.apnic.net   ALLOCATED
   127/8  IANA - Loopback                                1981-09                    RESERVED     [5]
   128/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   129/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   130/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   131/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   132/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   133/8  Administered by APNIC                          1997-03  whois.apnic.net    LEGACY
   134/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   135/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   136/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   137/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   138/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   139/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   140/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   141/8  Administered by RIPE NCC                       1993-05  whois.ripe.net     LEGACY
   142/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   143/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   144/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   145/8  Administered by RIPE NCC                       1993-05  whois.ripe.net     LEGACY
   146/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   147/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   148/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   149/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   150/8  Administered by APNIC                          1993-05  whois.apnic.net    LEGACY
   151/8  Administered by RIPE NCC                       1993-05  whois.ripe.net     LEGACY
   152/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   153/8  Administered by APNIC                          1993-05  whois.apnic.net    LEGACY
   154/8  Administered by AfriNIC                        1993-05 whois.afrinic.net   LEGACY
   155/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   156/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   157/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   158/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   159/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   160/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   161/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   162/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   163/8  Administered by APNIC                          1993-05  whois.apnic.net    LEGACY
   164/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   165/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   166/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   167/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   168/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   169/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY      [6]
   170/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY
   171/8  Administered by APNIC                          1993-05  whois.apnic.net    LEGACY
   172/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY      [7]
   173/8  ARIN                                           2008-02  whois.arin.net    ALLOCATED
   174/8  ARIN                                           2008-02  whois.arin.net    ALLOCATED
   175/8  APNIC                                          2009-08  whois.apnic.net   ALLOCATED
   176/8  IANA                                                                     UNALLOCATED
   177/8  IANA                                                                     UNALLOCATED
   178/8  RIPE NCC                                       2009-01  whois.ripe.net    ALLOCATED
   179/8  IANA                                                                     UNALLOCATED
   180/8  APNIC                                          2009-04  whois.apnic.net   ALLOCATED
   181/8  IANA                                                                     UNALLOCATED
   182/8  APNIC                                          2009-08  whois.apnic.net   ALLOCATED
   183/8  APNIC                                          2009-04  whois.apnic.net   ALLOCATED
   184/8  ARIN                                           2008-12  whois.arin.net    ALLOCATED
   185/8  IANA                                                                     UNALLOCATED
   186/8  LACNIC                                         2007-09 whois.lacnic.net   ALLOCATED
   187/8  LACNIC                                         2007-09 whois.lacnic.net   ALLOCATED
   188/8  Administered by RIPE NCC                       1993-05  whois.ripe.net     LEGACY
   189/8  LACNIC                                         1995-06 whois.lacnic.net   ALLOCATED
   190/8  LACNIC                                         1995-06 whois.lacnic.net   ALLOCATED
   191/8  Administered by LACNIC                         1993-05 whois.lacnic.net    LEGACY
   192/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY     [8][9]
   193/8  RIPE NCC                                       1993-05  whois.ripe.net    ALLOCATED
   194/8  RIPE NCC                                       1993-05  whois.ripe.net    ALLOCATED
   195/8  RIPE NCC                                       1993-05  whois.ripe.net    ALLOCATED
   196/8  Administered by AfriNIC                        1993-05 whois.afrinic.net   LEGACY
   197/8  AfriNIC                                        2008-10 whois.afrinic.net  ALLOCATED
   198/8  Administered by ARIN                           1993-05  whois.arin.net     LEGACY      [10]
   199/8  ARIN                                           1993-05  whois.arin.net    ALLOCATED
   200/8  LACNIC                                         2002-11 whois.lacnic.net   ALLOCATED
   201/8  LACNIC                                         2003-04 whois.lacnic.net   ALLOCATED
   202/8  APNIC                                          1993-05  whois.apnic.net   ALLOCATED
   203/8  APNIC                                          1993-05  whois.apnic.net   ALLOCATED    [11]
   204/8  ARIN                                           1994-03  whois.arin.net    ALLOCATED
   205/8  ARIN                                           1994-03  whois.arin.net    ALLOCATED
   206/8  ARIN                                           1995-04  whois.arin.net    ALLOCATED
   207/8  ARIN                                           1995-11  whois.arin.net    ALLOCATED
   208/8  ARIN                                           1996-04  whois.arin.net    ALLOCATED
   209/8  ARIN                                           1996-06  whois.arin.net    ALLOCATED
   210/8  APNIC                                          1996-06  whois.apnic.net   ALLOCATED
   211/8  APNIC                                          1996-06  whois.apnic.net   ALLOCATED
   212/8  RIPE NCC                                       1997-10  whois.ripe.net    ALLOCATED
   213/8  RIPE NCC                                       1993-10  whois.ripe.net    ALLOCATED
   214/8  US-DOD                                         1998-03                     LEGACY
   215/8  US-DOD                                         1998-03                     LEGACY
   216/8  ARIN                                           1998-04  whois.arin.net    ALLOCATED
   217/8  RIPE NCC                                       2000-06  whois.ripe.net    ALLOCATED
   218/8  APNIC                                          2000-12  whois.apnic.net   ALLOCATED
   219/8  APNIC                                          2001-09  whois.apnic.net   ALLOCATED
   220/8  APNIC                                          2001-12  whois.apnic.net   ALLOCATED
   221/8  APNIC                                          2002-07  whois.apnic.net   ALLOCATED
   222/8  APNIC                                          2003-02  whois.apnic.net   ALLOCATED
   223/8  IANA                                                                     UNALLOCATED
   224/8  Multicast                                      1981-09                    RESERVED     [12]
   225/8  Multicast                                      1981-09                    RESERVED     [12]
   226/8  Multicast                                      1981-09                    RESERVED     [12]
   227/8  Multicast                                      1981-09                    RESERVED     [12]
   228/8  Multicast                                      1981-09                    RESERVED     [12]
   229/8  Multicast                                      1981-09                    RESERVED     [12]
   230/8  Multicast                                      1981-09                    RESERVED     [12]
   231/8  Multicast                                      1981-09                    RESERVED     [12]
   232/8  Multicast                                      1981-09                    RESERVED     [12]
   233/8  Multicast                                      1981-09                    RESERVED     [12]
   234/8  Multicast                                      1981-09                    RESERVED     [12]
   235/8  Multicast                                      1981-09                    RESERVED     [12]
   236/8  Multicast                                      1981-09                    RESERVED     [12]
   237/8  Multicast                                      1981-09                    RESERVED     [12]
   238/8  Multicast                                      1981-09                    RESERVED     [12]
   239/8  Multicast                                      1981-09                    RESERVED     [12]
   240/8  Future use                                     1981-09                    RESERVED     [13]
   241/8  Future use                                     1981-09                    RESERVED     [13]
   242/8  Future use                                     1981-09                    RESERVED     [13]
   243/8  Future use                                     1981-09                    RESERVED     [13]
   244/8  Future use                                     1981-09                    RESERVED     [13]
   245/8  Future use                                     1981-09                    RESERVED     [13]
   246/8  Future use                                     1981-09                    RESERVED     [13]
   247/8  Future use                                     1981-09                    RESERVED     [13]
   248/8  Future use                                     1981-09                    RESERVED     [13]
   249/8  Future use                                     1981-09                    RESERVED     [13]
   250/8  Future use                                     1981-09                    RESERVED     [13]
   251/8  Future use                                     1981-09                    RESERVED     [13]
   252/8  Future use                                     1981-09                    RESERVED     [13]
   253/8  Future use                                     1981-09                    RESERVED     [13]
   254/8  Future use                                     1981-09                    RESERVED     [13]
   255/8  Future use                                     1981-09                    RESERVED   [13][14]
Taken from iana.org , for more information regarding the notes field, please take a look at the hyperlinked url above.

As you can see, there are several different designations for each range. These are mainly the regional providers. There are 5 Regional Providers, AfriNIC, APNIC, ARIN, LACNIC, RIPE NCC. They cover the following areas, Africa, Asia and Pacific, North America, Latin America and the Caribbeans, Europe along with the Middle East and Central Asia, respectively.

The Internet Engineering Task Force is also a high contributor in this process, they work closely with several departments in regards to Internet Standards. Including but not limited to, W3C, ISO, IEC, and other agencies that are either governmental or not. Many of their members also currently have written several RFC technical data's.

Useful content:

Premium Member
8,052 Posts
Discussion Starter #6
Internet Infrastructure

While the Internet is a network infrastructure compromised of several routers, hubs, gateways, switches the hardware is incredibly different then what we use. An example of a carrier-grade router below (Cisco CRS-1, Juniper MX960):

Some of these devices can route millions of packets per second and commonly have optical interfaces up through but not limited to OC-768 (~40 Gbps). These machines use certain protocols such as Border Gateway Protocol (BGP), Open Shortest First Path (OSPF) and/or Intermediate System-to-Intermediate System (IS-IS, yes it is still in use today) to exchange routing information between networks and varying locations. BGP is the protocol responsible for the maintaining the majority of routing on the Internet. These routers are typically interconnected through fiber optic line laid through cities, country sides, etc.

Just like any local network but on a larger geographical scale, ISPs also have backbone and access layer (PE or Provider Edge) implementations. If you order a circuit or internet connection, the cabling from your location and WAN-facing interface typically makes it back to an interface on one of these devices. For a provider, it is common to 'multiplex' (mux) enterprise grade connections into a single interface. For example, a provider can break a T3/DS3 interface (44.736 Mbit) into 28 separate T1/DS1 (1.544 Mbit) for multiple various customers.

While these devices have implemented their own complexities, they still use the same TCP/IP protocol suite that your router at home uses to transmit and receive data.

Premium Member
8,052 Posts
Discussion Starter #7
Protocols, OSI and TCP/IP Layer Models, and Packets


The OSI Model
The OSI Model was the original foundation of networking as it is known today. The TCP/IP layer is based off of this model. The model's full name is known as the Open Systems Interconnection imitative. There are two contributing factors to this model, the Basic Reference Model and a specific set of Protocols. The OSI Model was developed and is maintained by the International Organization for Standardization. Every layer utilizes its own unique features and brings something different to the table.
OSI Model:
  • Application - This layer in the OSI model, is geared specifically for functions that do not exist in the Presentation or Session layer in regards to protocol implementations. Several of these protocols include:
    Bittorrent,P2P, BOOTP, DHCP, DNS, IMAP, RTP, RPC, SSH, Telnet, VTP, SMTP SMB, OSCAR (AIM), And more
    This layer is present in both the OSI Model and the TCP/IP Model.
  • Presentation - This layer is representative of how the data is formatted, coded, and delivered. It alleivates the need for the Application layer to worry about data, syntax, conversion needs going down the model.
    • Common Application Service Element (CASE) - Usually, common applications are provided with a application specific element that is needed among a variety of programs. In many cases, several CASEs are used by only one application. There are four CASEs that are defined in the OSI Specification, Association Control Service Element, Remote Operations Service Element, Reliable Transfer Service Element, and Commitment, concurrence, and recovery serivce aelements. These all co-ordinate with specific responsibilities in regards to protocols.

      Originally Posted by http://www.cisco.com/en/US/docs/internetworking/technology/handbook/OSI-Protocols.html
      Association control service element (ACSE)-Creates associations between two application entities in preparation for application-to-application communication
      Remote operations service element (ROSE)-Implements a request-reply mechanism that permits various remote operations across an application association established by the ACSE
      Reliable transfer service element (RTSE)-Allows ASEs to reliably transfer messages while preserving the transparency of complex lower-layer facilities
      Commitment, concurrence, and recovery service elements (CCRSE)-Coordinates dialogues among multiple application entities.
    • Specific Application Service Element (SASE) - This sublayer are ASE's that provide a function used only by the corresponding application Process ID. These can include file transfer, database access, or order functions. There is a wide array of what these can provide and what they function with.
  • Session - The session layer is responsible for synchronizing, collaborating, establishing different streams and making sure that the information is kept on a continuing established connection. A prime example of this is when two video conferencing applications are set up and have an established connection. Say for instance you have Skype up, you see the lips moving, but the audio is two or three seconds late. The Session layer helps keep this syncronized when talking. Another prime example is when using Ventrilo, when you key up to talk, the speaker is green, however at times when you have a high ping, the speaker is yellow and it will take a couple of seconds for it to light up as green.
  • Transport - This layer is the basic set of rules of transporting packets to and from their destination.
    Here is a comparison chart taken from wikipedia and implemented into Google Spreadsheets that shows the TCP/IP Protocols and their services and features they offer.

    http://spreadsheets.google.com/pub?key=tRD85CC8F4D7uElM4lUXx1Q&w=50&h=300 Google Spreadsheet

    Again taken from wikipedia

    The OSI model defines five classes of connection-mode transport protocols designated class 0 (TP0) to class 4 (TP4). Class 0 contains no error recovery, and was designed for use on network layers that provide error-free connections. Class 4 is closest to TCP, although TCP contains functions, such as the graceful close, which OSI assigns to the Session Layer. All OSI connection-mode protocol classes provide expedited data and preservation of record boundaries. Detailed characteristics of the classes are shown in the following table.

    http://spreadsheets.google.com/pub?key=twpBvRJ4YGIe5kfUhqzLHIQ&w=40&h=490 Google Spreadsheet

  • Network - This layer controls IP Addressing (,, etc), Message Forwading, and Connection-oriented and Connectionless communication. Message forwarding is the use of a router or gateway to forward and send packets between networks. In many textbooks, and even in Cisco classes, this layer is often associated with the Internet Layer. While a helpful way to study, the classification is wrong due to the differences between protocols of the two Models. This is when the data is referred to as a Packet.
  • Datalink - This layer has two sublayers which are important to both Wide Area Networks, and Local Area Networks. The Data Link layer itself allows for data transfer among two adjacent networking nodes or segments. The frame can change depending on how much information the higher layers need to send or add in overhead for TCP.
    • Logical Link Control (LLC) - This upper sub-layer allows multiple protocols to exist within the same network, and to be allowed to flow and be transferred over the same networking media, such as an Network Interface Card. It does this using multiplexing and flow control. This layer is also responsible for error checking, if it is enabled and notified in the request.
    • Media Access Control (MAC)- This lower sub-layer provides physical addressing, and channel access control so that a device can communicate together while multiple devices exist. This typically is used in a Local Area Network (LAN), or Metropolitan Area Network(MAN). The addressing mechanism used here is commonly referred to as the MAC Address or the Physical Address. Since a MAC address is a unique number, there will never be two devices that have the same MAC address unless configured as such.
  • Physical - This layer is associated with hardware, media, signal, and transmission. The Data Unit here used is a bit, a 1 or 0. Probably by far the most complex layer for the OSI model.
The TCP/IP Model
The TCP/IP Layer was created by the United States Department of Defense under the section of DARPANET. Originally evolving from the original basic internet, of which was a wide area network, called Arpanet. In most networking classes I have been in, the first word you will hear associated with this is usually the DoD or the Internet model.
TCP/IP Model:
  • Application Layer - Is responsible for such protocols as; http,e-mail, ftp, p2p, etc.
  • Transport Layer - This layer is responsible for directing packets, error correction, flow and segmentation control, and port addressing.
  • Internet Layer - Is the solution for sending data between one or more networks. This relies heavily on IP Addressing and Routing.
  • Hardware Layer - Converts binary code into a usable signal for traveling across medias such as Cat5e, Copper Cabling, Fiber-Optics, etc.
Dissecting a packet to Overclock.net (large image):

In Hexadecimal form, the beginning of the packet looks like this:


0000  02 04 4b 14 d6 26 00 13  10 f9 4b 62 08 00 45 00   ..K..&.. ..Kb..E.0010  05 dc 41 c7 40 00 34 06  d1 ff 43 dc d4 73 0a 0a   [email protected] ..C..s..0020  0a fc 00 50 05 0a 54 65  a7 c3 e6 22 0f 89 50 10   ...P..Te ..."..P.0030  1e ae d5 0c 00 00 48 54  54 50 2f 31 2e 31 20 32   ......HT TP/1.1 20040  30 30 20 4f 4b 0d 0a 44  61 74 65 3a 20 54 75 65   00 OK..D ate: Tue0050  2c 20 32 34 20 4e 6f 76  20 32 30 30 39 20 30 37   , 24 Nov  2009 070060  3a 35 31 3a 32 37 20 47  4d 54 0d 0a 53 65 72 76   :51:27 G MT..Serv0070  65 72 3a 20 41 70 61 63  68 65 0d 0a 58 2d 50 6f   er: Apac he..X-Po0080  77 65 72 65 64 2d 42 79  3a 20 50 48 50 2f 35 2e   wered-By : PHP/5.0090  31 2e 36 0d 0a 43 61 63  68 65 2d 43 6f 6e 74 72   1.6..Cac he-Contr00a0  6f 6c 3a 20 70 72 69 76  61 74 65 2c 20 6d 61 78   ol: priv ate, max00b0  2d 61 67 65 3d 30 0d 0a  50 72 61 67 6d 61 3a 20   -age=0.. Pragma: 00c0  70 72 69 76 61 74 65 0d  0a 58 2d 55 41 2d 43 6f   private. .X-UA-Co00d0  6d 70 61 74 69 62 6c 65  3a 20 49 45 3d 37 0d 0a   mpatible : IE=7..00e0  43 6f 6e 74 65 6e 74 2d  45 6e 63 6f 64 69 6e 67   Content- Encoding00f0  3a 20 67 7a 69 70 0d 0a  43 6f 6e 74 65 6e 74 2d   : gzip.. Content-0100  4c 65 6e 67 74 68 3a 20  33 38 35 31 39 0d 0a 45   Length:  38519..E0110  78 70 69 72 65 73 3a 20  54 75 65 2c 20 32 34 20   xpires:  Tue, 24 0120  4e 6f 76 20 32 30 30 39  20 30 37 3a 35 31 3a 32   Nov 2009  07:51:20130  37 20 47 4d 54 0d 0a 43  6f 6e 74 65 6e 74 2d 54   7 GMT..C ontent-T0140  79 70 65 3a 20 74 65 78  74 2f 68 74 6d 6c 3b 20   ype: tex t/html; 0150  63 68 61 72 73 65 74 3d  49 53 4f 2d 38 38 35 39   charset= ISO-88590160  2d 31 0d 0a 0d 0a 1f 8b  08 00 00 00 00 00 00 ff   -1...... ........0170  ec bd 69 77 db d6 d5 06  fa 39 5d ab ff e1 98 69   ..iw.... .9]....i0180  2b 27 15 48 02 e0 28 5b  f2 d5 68 ab d5 54 49 1e   +'.H..([ ..h..TI.0190  da dc 2c 05 24 41 11 16  09 30 00 28 8a e9 7b ff   ..,.$A.. .0.(..{.01a0  fb 7d f6 3e 00 08 90 e0  04 49 89 54 cb 19 4c 82   .}.>.... .I.T..L.01b0  38 f3 3e 7b 1e de be da  3b dd bd fc f7 d9 be e8   8.>{.... ;.......01c0  f8 bd ae 38 fb b8 73 74  b8 2b 72 4a a1 f0 59 df   ...8..st .+rJ..Y.01d0  2d 14 f6 2e f7 c4 97 0f  97 c7 47 42 cd 17 c5 a5   -....... ..GB....01e0  6b d8 9e e5 5b 8e 6d 74  0b 85 fd 93 9c c8 75 7c   k...[.mt ......u|01f0  bf bf 51 28 0c 87 c3 fc  50 cf 3b ee 75 e1 f2 bc   ..Q(.... P.;.u...0200  70 47 7d a9 d4 38 f8 a8  f8 b1 96 f9 96 df ca 6d   pG}..8.. .......m0210  fd f9 4f 6f 79 c4 bb 5e  d7 f6 36 53 fa 51 eb f5   ..Ooy..^ ..6S.Q..0220  ba 6c 9e 13 2d cb dd cc  75 7d 37 27 ba 86 7d bd   .l..-... u}7'..}.0230  99 33 6d d9 81 69 b4 d0  d1 77 6f 5f 29 8a b0 1d   .3m..i.. .wo_)...0240  d1 34 9a 1d 53 74 f0 d4  74 3d a1 28 fc 5b cf f4   .4..St.. t=.(.[..0250  0d 2c ce ef 2b e6 af 03  eb 76 33 77 e6 1a d7 3d   .,..+... .v3w...=0260  23 27 9a 8e ed 9b b6 bf  99 b3 1d 85 5b e6 44 21   #'...... ....[.D!0270  bd c5 fe 5d df 72 4d 2f  d6 44 51 67 be bc 4b 93   ...].rM/ .DQg..K.0280  50 76 d1 b9 eb 74 63 4d  26 47 a1 39 9b 76 6b e6   Pv...tcM &G.9.vk.0290  bc bb 96 7d 23 5c b3 bb  99 6b 1a b6 63 5b 4d 03   ...}#\\.. .k..c[M.02a0  bd 75 5c b3 9d d8 2c e7  d6 74 9b 5d a7 79 93 b7   .u\\...,. .t.].y..02b0  4d bf 40 93 fa d3 5b 5e  b1 6d f4 cc cd 1c 7e b5   [email protected][^ .m....~.02c0  da 23 e5 16 d3 8d 96 5b  e9 fd fd a6 5b 18 5c de   .#.....[ ....[.\\.02d0  1c 7d fe 62 9e 79 d7 e7  7a d1 fe a7 dd 1a 7e dc   .}.b.y.. z.....~.02e0  6b d5 ea e7 95 ff f4 ad  d3 ae f5 f9 e2 e4 d3 4d   k....... .......M02f0  73 33 27 e8 a0 a6 b6 90  56 87 ad 53 2e 47 7d 33   s3'..... V..S.G}30300  d6 b3 6f de f9 05 3a d5  37 a2 d9 31 5c cf f4 37   ..o...:. 7..1\\..70310  0f 2f 4e 95 5a ad 5c 0f  37 2c 3e b9 6b d3 36 5d   ./N.Z.\\. 7,>.k.6]0320  c3 77 70 ac d1 e4 6e 77  06 dd ae e9 5b b6 d0 f3   .wp...nw ....[...0330  b5 7c 49 ee 72 38 05 b9  a6 1b 73 34 74 dc 56 fc   .|I.r8.. ..s4t.V.0340  38 a2 5d b0 ec eb f5 e8  cb f8 93 68 3b ee a0 17   8.]..... ...h;...0350  fb de 74 7a fd 81 6f 62  64 3a f2 f8 a4 5a a6 d7   ..tz..ob d:...Z..0360  74 ad 3e 01 79 6c 5a db  b6 88 ba c5 18 b2 3f d1   t.>.ylZ. ......?.0370  32 6f 1d df 6c 09 df 11  3d e3 ce ea 59 bf d1 6f   2o..l... =...Y..o0380  3e 60 b0 6f ba 18 b2 67  d8 4d 53 38 6d 71 ed 1a   >`.o...g .MS8mq..0390  fd 8e d5 f4 00 a1 98 f8  ba d8 3d fb 88 ff f7 1c   ........ ..=.....03a0  bc ea 36 1c f9 ec 7c fb  58 18 80 07 13 67 36 f2   ..6...|. X....g6.03b0  3b d4 93 d9 f5 4c 0c 35  c0 53 0b 17 af 65 8a 91   ;....L.5 .S...e..03c0  33 70 b1 59 72 f2 e8 cd  33 f3 e1 16 61 19 04 52   3p.Yr... 3...a..R03d0  bb 17 17 e2 c2 1f 75 4d  af 63 9a be bc 04 6f 3d   ......uM .c....o=03e0  7a 20 7c 9c d6 66 8e 0f  a9 e9 61 fb ac 16 00 a4   z |..f.. ..a.....03f0  11 ec f7 15 3d c2 5e 14  7e fc f1 cf 7f fa 51 4c   ....=.^. ~.....QL0400  9c 03 75 4b 8f b9 e7 0d  b1 f6 99 26 f3 c9 32 87   ..uK.... ...&..2.0410  6b 6f e4 33 71 b8 b7 21  d4 12 de 29 fc f9 4f 0d   ko.3q..! ...)..O.0420  a7 35 fa f3 9f fe 8b 9b  d9 30 9a 37 d7 2e ad 60   .5...... .0.7...`0430  43 7c 5f aa 94 2b 95 9d  37 78 dc 74 ba 8e 8b 27   C|_..+.. 7x.t...'0440  6d fe 43 4f da 80 a8 0d  51 ef fb 02 cb 6f 19 b6   m.CO.... Q....o..0450  b1 2e 08 3c 6e f1 77 77  d0 b4 5a f8 7b 4d 7e a0   ...<n.ww ..Z.{M~.0460  cd b4 5b e6 da ba 30 5c  cb e8 ae e3 be 77 6f 01   ..[...0\\ .....wo.0470  31 4d bc e2 01 3f 29 1e  c1 3c f5 d9 33 dc 6b cb   1M...?). .<..3.k.0480  de 10 c5 fe 5d fc 3f fa  a9 6f b4 5a d8 61 fe 0d   ....].?. .o.Z.a..0490  df ff bf 3f ff c9 d8 a0  0b b7 2e 68 ee 57 06 7d   ...?.... ...h.W.}04a0  96 2b 08 a7 aa e1 4f 7d  37 7c f7 d6 02 1e 34 5b   .+....O} 7|....4[04b0  e1 eb c1 d7 79 2d 3a 04  3f 98 f3 86 d1 f4 ad 5b   ....y-:. ?......[04c0  33 6c c9 8f 93 ed 0e 0e  4a a5 62 51 8e 94 ef 1b   3l...... J.bQ....04d0  d7 e6 6a 5b 89 b5 f8 98  98 df 59 17 7d 6c 9e 25   ..j[.... ..Y.}l.%04e0  5b 3f c2 fe 62 a0 bc df  c0 4d 34 dd 94 19 56 6a   [?..b... .M4...Vj04f0  d5 52 4d a7 bd 0e 77 b0  c8 7f e8 89 6c 04 78 c1   .RM...w. ....l.x.0500  c1 78 4e d7 6a c5 60 83  7b 6d 1a 7e 4a 97 e8 70   .xN.j.`. {m.~J..p0510  67 bb 1c ef f2 80 ff d0  13 b9 be 86 d3 6d 3d 2c   g....... .....m=,0520  10 85 d3 c1 c1 49 f8 c8  fb 98 5c 1a 80 8c 61 99   .....I.. ..\\...a.0530  6e 98 d2 32 9b 0e 90 1b  d0 c8 06 50 bc 6d 62 92   n..2.... ...P.mb.0540  b1 be 22 f8 09 ba 4b 05  a0 95 7a 0c e0 8b fb 8b   .."...K. ..z.....0550  41 59 d0 7f 2a 98 1d 1c  54 2a b4 77 53 f3 c5 75   AY..*... T*.wS..u0560  35 5d 2c 37 9a 34 91 d4  94 03 29 97 ca 66 a5 b5   5],7.4.. ..)..f..0570  f0 40 54 ba 80 0f 76 ad  79 17 69 42 b1 23 a1 af   [email protected] y.iB.#..0580  69 67 12 c1 47 bc 51 6c  ef 65 bb d4 cd 4f 6d 1a   ig..G.Ql .e...Om.0590  6d 72 30 7e 78 97 f3 40  e4 34 83 19 db 7c 70 10   [email protected] .4...|p.05a0  9e 7e db 71 d2 20 7b 7c  35 c2 cb 92 1c 9e 9a c5   .~.q. {| 5.......05b0  96 4b 5f 17 2f 37 68 14  5b ae 6c b7 c4 72 83 a6   .K_./7h. [.l..r..05c0  d1 72 83 ef e3 e5 ca 9e  66 2c 97 a1 8a 76 dc e8   .r...... f,...v..05d0  fa ea ba e0 bf b6 19 eb  a5 c0 d0 41 99 fe 89 c3   ........ ...A....05e0  50 b4 19 41 17 9a ec 42  9b d9                     P..A...B ..
Now, you may be thinking that later stuff just looks like a bunch of jibberish, when will [email protected] ever be used in a transmission? Well, surprisingly, that is all a part of the TCP Segment data. Which contains the data transmission of the website. This is only a part of dozens of packets, each one has its similarities and differences.

Premium Member
8,052 Posts
Discussion Starter #8
Things to consider when you have Internet Problems

Taken from this thread with procpuarie's permission.


  • Have you connected the modem straight to your computer?
  • Do you have DSL line filters connected to all your phones running on the same phone line?
  • Is the telephone cable connecting your DSL modem to your phone jack less then six (6) feet long? Does it have any bare wires or damage?
  • How far away are you from your central office (click here)? Is it more then four (4) kilometers (2.5 miles)?
  • Do you live in an older area (older homes/telephone infrastructure)?
  • Is the telephone wiring poor in your house?

  • Have you connected the modem straight to your computer?
  • Is your modem connected to a coax splitter or smiler device?
  • Do you have a coax filter connected to your modem (or any line your modem runs through)?
  • Is the coax cable connected to your modem free of any bare wires or damage?
  • Is the modem of the correct version of DOCSIS for your line speed?
  • Is the coax wiring poor in your house?

Solutions to Common Problems

Internet Connectivity

  • Problem: You recently hooked up a router or new computer to your modem and your internet browser does not load pages.
Answer: Have you tried power-cycling your modem? Unplug the modem for thirty seconds, after thirty seconds plug it back in, depending on if you are running windows XP or Windows Vista/7 click Repair or Diagnose. Alternative you can use the cmd command:


ipconfig /releaseipconfig /renew
Or restart the computer.


  • Problem: You can currently connect to AIM, Skype, IRC, however you can not connect to websites.
Answer: There are several resolutions to this. You can reset the cable modem hoping that this attempts to fix the problem. You can reset the TCP/IP stack in Windows XP/Vista/7 using this command:
Windows XP:

This command allows you to output all actions to a log that will be saved on the C:\\ drive.


netsh int ip reset c:\
esetlog.txtnetsh winsock reset catalog
You could also use the program located here.
Windows Vista/7:


netsh winsock reset (make sure you are elevated or have disabled UAC)
For more information about the Windows netsh command, please read up on it here.

If you have done all the following, or if you can use another internet source such as a school, a neighbor (with their permission), etc, then it is most likely your ISP and something on their end. The only thing you can do in that instance is wait. The website/server could be down and not loading for anyone. If that is the case, I would try this site: http://downforeveryoneorjustme.com/.


  • Problem: Your game can not connect to a server, or you are having a hard time getting a game or application to work with the internet.
Answer: You may need to set up port forwarding for the specific application. Portforward.com has the most complete guides for games and applications and video game consoles. It is very easy, first choose your routers brand/model, and then wait or click through the advertisement, then select the program, game, or video game console you want to setup and then follow their guide.

As far as I am aware, they do not provide support for third-party firmware such as, DD-WRT, Tomato, pfsense, untangled, etc.

Networking Connectivity

  • Problem: You are trying to turn your Wireless Home Router into a Wireless Access Point to extend range. Whatever reason though, you are having issues setting it up.

    Answer: Most home routers can normally be set up as limited, or complete Wireless Access Points. How do you do this you ask? Look below.
    Thanks to Enterprise for his picture
    1. Log into your router using it's IP address. You can accomplish this by going to your browser. Finding the URL Bar, and inputting it there.
    2. You will then be prompted for a username and password. These differ for each firmware, and model/manufacturer of router. So read the manual for instructions in this case.
    3. You will be prompted with this screen (Looks similar in almost all instances for Linksys routers)
    4. You should see Internet Connection Type for most routers, this should either be left as is or set to disabled if that is an option.
    5. For the Local IP Address, change it to something outside of the DHCP Range of your current router. So, if Router 1 has a DHCP Range of 50 Addresses, and it starts at any IP range from to will work.
    6. Now, go to the Security Tab and disable the Firewall so that it has the following items disabled:
      Thank you coldrush for the below picture.
    7. Now, finally go into your NAT/QoS tab. You will need to disable any port forwarding, UPnP, or Quality Of Service you have set up.
    8. Now, go to the Wireless tab. And put the SSID that you want to repeat.
      So, for example, say Router 1's Wireless SSID is ABCDEFG, and you want to extend it's range on Router 2. Go to the Wireless tab on Router 2 and use the Wireless SSID as ABCDEFG. Make sure that you don't use the same Wireless Channel, on both routers, or there will be errors/issues with being able to connect. Preferably, you always want to use channels seperate from each other, so, Router 1 is broadcasting on Channel 1, you would preferably want Router 2 to broadcast on Channel 11. If you have three or more routers, you would want to rotate the channel broadcasting, Router 1 broadcasting on channel 1, Router 2 broadcasting on channel 6, Router 3 broadcasting on channel 11, Router 4 broadcasting on Channel 1, and so on.
    Third-party firmware, such as DD-WRT, or Tomato, have guides already written out on how to accomplish this. Listed here (DD-WRT) is a decent one already written on how to configure a DD-WRT enabled router to become a Wireless Access Point.

Mr. Nude_Lewd_Man's troubleshooting guide for xDSL and Virgin Media (as attached in a post below)

How to troubleshoot Internet Connection Issues with xDSL
Written by: Nude_Lewd_Man, 16 Dec 09

Description of why you would be performing this task:

A user can't access the internet.

Procedures and steps

1. Check what type of connection the user has to their 'router'. Most of the following relate to modem/router/firewall/switch combination devices, and although most can also be replicated for other xDSL connections, those who use Virgin Media (formerly NTL or Telewest) or 3G USB dongles have different steps.

2. Ask the user to PING the router. Get them to go Start > Run > type "cmd" > [Enter] > type "ipconfig" > [Enter] > note the "Gateway" address > type "PING <router IP>" [Enter]. Also ask them to PING an external IP - you can ping a site from your computer and give them the IP for them to "PING <IP>" [Enter]&#8230;

3. While they're doing this, try to connect onto their computer, if you can connect then it is likely to be a DNS issue. It is also advisable to check whether they are connected by wirelessly or with an ethernet/network cable.

4. If you can't connect, ask them to go to the router. Get them to tell you which lights are flashing, and what colour the lights are. Bear in mind that normally only one of the <number> lights will blink (in orange on ZyXELs) per computer that has an active wired connection.

5. If there is no blinking LED for the internet light, ask them to turn the router off, wait 10 seconds and power it back up again. This normally takes around 1-3 minutes to get back to full operational state. (For USB xDSL modems, get the user to remove the USB cable from their computer for 10 seconds)

6. Ask them to keep you updated with which lights are flashing; you mainly want to know about the DSL/Internet LED. This is likely to flicker up green at first, if it goes orange this points towards there being an issue.

7. A lot of, but not all, users should have a (analogue) handset in their location, as them to pick this up and let you know whether there is a dial tone. It is a good idea to get the user to confirm that there is a 'ADSL Filter' in place: there needs to be on between each wall (phone) socket and any telecommunication device - voicemail, Sky (TV) boxes can all count, as do some 'monitored' alarms.

8. If there isn't a dial tone, or if the line has a lot of noise/crackle, then this points to an issue with the line. If there is a tone but it is noisy, check whether there is a spare filter and ask them to swap this with the one currently in use, then try the line again.

9. If there isn't a dial tone, or if the line is still noisy/crackly after changing the filter, this needs to be taken up with BT. Check www.bt.com for contact details, and get in touch. If there is no dial tone, this could be that the bill hasn't been paid or that there is an infrastructure fault - the latter needs to be dealt with by BT OpenReach.

10. If there is no (unusual) noise, you can test how far the connection can get by using some special credentials, but this would need to be done on site (unless they have access into the router's configuration pages). These credentials follow. Ensure you have the user take down their Login Name (paste into Notepad/etc) before getting them to change it in the router.

http://spreadsheets.google.com/pub?key=t_P8bQ7Lx6cASX7VG0UHloA&w=75&h=200 Google Spreadsheet

The credentials above can only access a VERY limited number of pages, which are listed here:
www.bt.net/digitaldemo (
http://speedtester.bt.net (

As a brief explanation of the above see the image below:

How to troubleshoot Internet Connection Issues with Virgin Media
Written by: Nude_Lewd_Man, 16 Dec 09

Description of why you would be performing this task:

A user can't access the internet.

Procedures and steps

Virgin doesn't use xDSL, but can provide digital television through their single cable to the property. The internet will/can also be carried through this same cable; connection is made by the cable modem to the Virgin Media servers/network directly and there is no password on the internet account.
  1. As in step 2 above, get the user to ensure that they have a (valid) IP address, and get them to PING their gateway IP address. Again, it is a good idea to give them the IP of an internet site (that allows PING replies) to test the connection.
  2. Below is an image of a Virgin Cable Modem. It should have the "power", "enet", "sync" and "ready" lights on. If any of these lights aren't on, then this will need to be restarted. If the user has this and also a firewall/switch/WAP between their computer and the cable modem, then this normally/often needs to be restarted too. If they connect their computer directly to this box, then disconnect the network cable.
  3. If it does need to be restarted, then power down the cable modem and any firewall/switch device connected to it. After about 30 seconds, they can restart the cable modem.
  4. While the cable modem is starting up, the lights will flicker and go off. Once the "sync" light has stabilised (to permanently on) and then the "ready" light has done the same, the user should then start any other device/s that were powered down, before finally restarting/reconnecting any other computers/devices. (The reason for this is that (in the past at least) Virgin/NTL/Telewest used to 'lock down' their connections to the MAC address of the first device after the cable modem.)
  5. If the "sync" and/or "ready" light don't go on, or aren't constant, then the user will need to get in touch with Virgin Media. They should be able to dial 150 (from their Virgin Media telephone), otherwise their contact details should be found on their website http://www.virginmedia.com/

Premium Member
8,052 Posts
Discussion Starter #10
If anyone has anything they would like included in the Networking or Internet Connectivity issues, please feel free to comment or drop me a PM of what you want added. I will do my best to make it understanding and comprehensible for all.

Feel free to comment, I do realize that the Internet Infrastructure was not very well explained. I am currently looking through several material to expand on that further.

Hope you enjoy reading it, if you can understand it.


3,289 Posts
Here are a couple of troubleshooting guides I've (just split from the original, as that was too big for a single attachment, but have) created at a couple of places I've worked - which I've used the training at an ISP and general troubleshooting I've done to write....

One is for ADSL (but can prolly be generalised for xDSL, as per the name) and the other is for Virgin connections. This is certainly good enough for getting UK internet connections sorted out, but a lot of what is in there should be transferable to other countries...

795 Posts
I think this is a great idea I would change a few things though. A that a switch create's networks where as a router combines networks. (And if I am wording this correctly trying to remember this of the top of my head) a switch creates separate collision domains and a router connects broadcast domains.

1,192 Posts
Fantastic in-depth article, the only this I can suggest adding is some info on how DNS and TLD's work/are administered.

I've only managed to pick up the one typo, good work
Originally Posted by GH0;7656174
  • Hub
    ...It accomplishes this by, rfeceiving the data at one port...

Premium Member
8,052 Posts
Discussion Starter #15
It will be updated when I get the time. Most likely when I get out of school for the summer.

2,203 Posts
I have been wondering, what does the "internet"'s MAIN server look like? (the machine that actually chucks around the internet to other computers)


3,289 Posts
Originally Posted by jdcrispe95;12232201
I have been wondering, what does the "internet"'s MAIN server look like? (the machine that actually chucks around the internet to other computers)


Top result:

The Internet is a global system of interconnected computer networks that use the standard Internet Protocol Suite (TCP/IP) to serve billions of users worldwide. It is a network of networks that consists of millions of private, public, academic, business, and government networks, of local to global scope, that are linked by a broad array of electronic, wireless and optical networking technologies.
There is no such thing as "the internet's main server". INTERconnected NETworks...the clue is in the name..

1,414 Posts
Originally Posted by Nude_Lewd_Man;12232494

Top result:

There is no such thing as "the internet's main server". INTERconnected NETworks...the clue is in the name..
Unless he is asking what one of the Root Servers (i.e. .com,.net,.gov...) looks like, but you are correct. INTERconnected NETworks means just that, networks connected together.

3,289 Posts
Originally Posted by bratas;12238426
Unless he is asking what one of the Root Servers (i.e. .com,.net,.gov...) looks like, but you are correct. INTERconnected NETworks means just that, networks connected together.
Possibly, but they were asking for the main SERVER rather than a TLD's infrastructure....
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