USRobotics Instant802 APSDK manual Supported Rate Set, Tcp/Ip, Tkip, ToS

Professional Access Point

Administrator Guide

The subnet mask allows a router to quickly determine if an IP address is local or needs to be forwarded by performing a bitwise AND operation on the mask and the IP address. For example, if an IP address is 192.168.2.128 and the netmask is 255.255.255.0, the resulting Network address is 192.168.2.0.

The bitwise AND operator compares two bits and assigns 1 to the result only if both bits are 1. The following table shows the details of the netmask:

IP address	192.168.2.128	11000000 10101000 00000010 10000000
Netmask	255.255.255.0	11111111 11111111 11111111 00000000
Resulting network address	192.168.2.0	11000000 10101000 00000010 00000000

Supported Rate Set

The supported rate set defines the transmission rates that are available on this wireless network. A station may be able to receive data at any of the rates listed in this set. All stations must be able to receive data at the rates listed in the Basic Rate Set.

T

TCP

The Transmission Control Protocol (TCP) is built on top of Internet Protocol (IP). It adds reliable communication (guarantees delivery of data), flow-control, multiplexing (more than one simultaneous connection), and connection-oriented transmission (requires the receiver of a packet to acknowledge receipt to the sender). It also guarantees that packets will be delivered in the same order in which they were sent.

TCP/IP

The Internet and most local area networks are defined by a group of protocols. The most important of these is the Transmission Control Protocol over Internet Protocol (TCP/IP), the de facto standard protocols. TCP/IP was originally developed by Defense Advanced Research Projects Agency (DARPA, also known as ARPA, an agency of the US Department of Defense).

Although TCP and IP are two specific protocols, TCP/IP is often used to refer to the entire protocol suite based upon these, including ICMP, ARP, UDP, and others, as well as applications that run upon these protocols, such as telnet, FTP, etc.

TKIP

The Temporal Key Integrity Protocol (TKIP) provides an extended 48-bit initialization vector, per-packet key construction and distribution, a Message Integrity Code (MIC, sometimes called "Michael"), and a rekeying mechanism. It uses a RC4 stream cipher to encrypt the frame body and CRC of each 802.11 frame before transmission. It is an important component of the WPA and 802.11i security mechanisms.

ToS

TCP/IP packet headers include a 3-to-5 bit Type of Service (ToS) field set by the application developer that indicates the appropriate type of service for the data in the packet. The way the bits are set determines whether the packet is queued for sending with minimum delay, maximum throughput, low cost, or mid-way "best-effort" settings depending upon the requirements of the data. The ToS field is used by the Professional Access Point to provide configuration control over Quality of Service (QoS) queues for data transmitted from the access point to client stations.

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