This article describes local area networking protocols and APIs, including NetBEUI, NETBios, TCP, IP, IPX, SPX, ARP, RARP, RIP, SNMP, DLC, IPX/SPX, NDIS, ODI, AND TDI.
|NetBEUI||Net Bios Extended User Interface||Transport|
|TCP||Transmission Control Protocol||Transport|
|IP||Internet protocol||Network layer|
|IPX||Internet Packet Exchange||Network layer|
|SPX||Sequenced Packed Exchange||Transport layer|
|ARP||Address Resolution Protocol||Maps Network layer (3) addresses to data link layer (2), or IPS addresses to MAC addresses, or Logical addresses to physical addresses|
|RARP||Reverse Address Resolution Protocol||Maps Data-link layer (2) to network layer (3), or MAC addresses to IP addresses, or Physical addresses to logical addresses|
|RIP||Routing Information Protocol||Updates entries in a routing table|
|SNMP||Simple Network Management Protocol||Provides performance, error, and other analysis and trouble-shooting information (Network Management [and switches] (Sportack, p.152)|
|00000000||00000000||00000000||00000001||Up to 256 combo's of 8 bits|
|255||255||255||255||256 to 4th power, or 2 to 32nd power=4.3 billion combo's|
|First Quad||Second Quad||Third Quad||Fourth Quad||Use|
|0XXXXXXX AAAAAAAA||LLLLLLLL||LLLLLLLL||LLLLLLLL||Class A [0-126] 127 Class A Networks. Each with possible 16 million host addresses (224)|
|01111111||Reserved , Loopback address. Only one, which wasted 24 million addresses|
|10XXXXXX AAAAAAAA||AAAAAAAA||LLLLLLLL||LLLLLLLL||Class B [128-191] Each of 16,384 Class B Networks get 60%,535 host addresses|
|110XXXXX AAAAAAAA||AAAAAAAA||AAAAAAAA||LLLLLLLL||Class C (192-223) Up to 254 hosts on 2,097,152 Class C Networks|
|1110XXXX||Reserved multicast addresses [224-239]|
|1111XXXX||Reserved, experimental addresses [240-255]|
|127.0.0.1||Loopback to current host|
|192.168.10.1||Default Gateway (Router)|
|192.168.10.3 -192.168.10.10||Manually or dynamically assigned to workstations in A_Domain|
|192.168.10.13 -192.168.10.30||Manually or dynamically assigned to workstations in B_Domain|
|192.168.10.255||IP Broadcast Address (all binary one's)|
A network segment is a physical division, set off by switches/routers. All it means is it's a broadcast area, i.e. broadcasts will go to an entire network segment.
A subnet is a logical organization method for IP networking (also IPX, I believe). You can have multiple subnets running on a single hub even.
Example: In Newport, all the PCs are on 155.42.140.x and all the Macs are on 155.42.139.x. Doesn't matter that a Mac and a PC can sit next to each other and be plugged into the exact same hub. The router in the closet knows that these two subnets are local, and handles the interchange between the two.
A subnet mask is a number that defines what part of an IP address refers to the network (subnet), and which part refers to the host (node).
IP addresses can be manually assigned to machines using the Networking Applet in Win9x and NT.
When addresses are assigned manually, they are called static IP addresses.
On larger networks, the 254 addresses available to a class C license are inadequate to provide an IP to every seat, so hosts which are not actually connected to the Internet use private network IP addresses.
The standard private network addresses (which are not passed along by routers) are standard ranges of addresses which any network can assign to hosts which are not being connected to the Internet.
Reasons for using private network addresses on our networks:
Private Network Addresses
Dynamically assigned IP addresses offer two advantages over static addresses:
A server running the Dynamic Host Configuration Protocol (DHCP) dynamically assigns IP addresses to clients.
DHCP does NOT relate host names to IP addresses. This is the job of DNS and WINS
Setting up DHCP on NT Server
Settings needed on the workstation
How does it work? See Minasi, p.933.
Four steps in client getting an IP Address from a DHCP server:
Service Pack 4 makes at least 6 improvements to the DCHP service.
The DCHP database should be backed up so that if the DCHP machine buys the farm another one can be put up and running.
Because IP addresses are not the easiest things to remember, and, indeed, because they may always be changing, we associate a word-like naming system with the actual IP addresses needed by the network protocols to create communications between computers and networks.
WINS (Windows Internet Naming Service)
WINS is only recognized by MS software, so it works for resolution inside your network/intranet (Minasi, p. 939WINS provides name resolution for NetBIOS names in a routed environment, while DNS's job is provide name resolution for WinSock names in a routed environment. (Minasi p.939).
See Minasi pp.938-955 for full discussion of WINS.
See Andrews, p.944).
Sockets relate to the OSI Application Layer.
(See Diagram of TCP/IP Protocol Suite, Andrews p.944).
Sockets are connections made between programs on one computer and those on another computer. They have three parts to them:
UDP is a connectionless protocol, it is used to broadcast messages when no response is required. Example of an application for UDP is mapping network drives. Error correction is not done by UDP, it must be provided by the application using it.
Error correction maps to the OSI Transport Layer)
(See Diagram of TCP/IP Protocol Suite, Andrews p.944).
IP is a routing protocol, TCP is a connection protocol, which means that it is there to provide end-to-end integrity.
TCP uses AKS's and NAK's to ensure that all packets are delivered and delivered in an undamaged state. It uses the IP's header checksum to determine if a packet is a good one.
Address Resolution relates to the OSI Network Layer)
(See Diagram of TCP/IP Protocol Suite,
|ARP||Address Resolution Protocol||Converts (logical) IP addresses into physical network addresses, i.e. MAC addresses.|
|RARP||Reverse Address Resolution Protocol||Converts physical addresses (MAC) to (logical) IP addresses.|
Often used by Token-Ring networks to make their PC workstations talk to mainframe gateways, many (but not all) of which require DLC.
Also used to communicate with network printers. Eg. Use DLC to control a laser printer attached directly to the network with a JetDirect print server (network interface) card.
Supported by NT.
"The most popular local area network type in the world is Novell Netware". (Minasi, p.81)
Supported by NT beginning with NT 4.(as part of the NetWare Compatible Services.
Like TCP/IP, IPX is routable and enjoys widespread support, but TCP/IP provides Internet connectivity.
Loading more than one protocol at a time permits connecting with diverse servers (Novell/MS), mainframe gateways, and routers (internet mail).
Example: the NT Network Stack:
|NDIS||Network Driver Interface Specification||Interfaces data-link layer to (Network) (Transport) layer||Microsoft|
|ODI||Open Data-Link Interface||Interfaces data-link layer to (Network) (Transport) layer||Novell
Will not load high
|TDI||Transport Driver Interface||Makes API's such as Winsock and NetBios protocol independent|
Bindings interface the NIC software driver with a network transport protocol.
This way one driver can be written to the interface's standard and can then communicate with any higher-level transport protocol.
Application Programming Interface. Primitive commands which are used by programmers to access (network) operating system services. Examples:
|NetBIOS||Microsoft "native" network API. A set of 18 commands.|
|TCP/IP Sockets||The preferred API for working over the Internet. On PC's and in NT the standard used is called WinSock.|
|Novell Sockets||Novell's API|