Automatic rate selection and rate scaling – Dell 4350 Network Access Point User Manual
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with each other.
The Dell Wireless 4350 Small Network Access Point uses either hexadecimal digits or ASCII characters to create encryption keys.
Hexadecimal digits include the numbers 0 to 9 and the letters A to F. For example, the decimal number 15 is represented as F in
the hexadecimal numbering system.
ASCII is the acronym for the American Standard Code for Information Interchange. Pronounced ask-ee, ASCII is a code for
representing English characters as numbers, with each letter assigned a number from 0 to 127. For example, the ASCII code for
uppercase M is 77. Most computers use ASCII codes to represent text, which makes it possible to transfer data from one computer
to another.
WPA
WPA (Wi-Fi Protected Access) is an upgrade to the WEP standard for securing your wireless network. WPA is derived from and
will be forward-compatible with the future IEEE 802.11i standard. It provides improved data encryption and user authentication.
To enhance the level of security, WPA uses Temporal Key Integrity Protocol (TKIP) encryption to address the vulnerabilities of
the static keys used in WEP. TKIP includes four algorithms: message integrity check (MIC), to protect packets from tampering;
Per-Packet Key (PPK) hashing, to prevent weak key attacks; extended initialization vector (IV), to reduce IV reuse and the
possibility that a hacker will collect sufficient packets to crack the encryption; and a re-keying mechanism, to change the temporal
key dynamically. TKIP is the most commonly used encryption method; however, if your wireless clients do not support TKIP, the
Wireless 4350 also supports Advanced Encryption Security (AES) encryption. AES will replace 802.11's RC4-based encryption
under the 802.11i specification. AES, the gold-standard encryption algorithm, provides maximum security for wireless network.
For user authentication, WPA adopts an authentication scheme through 802.1x. 802.1x provides a framework for user
authentication and a key distribution management method. 802.1x consists of three main elements: an Authentication Server
(typically a RADIUS server), WPA-enabled router or AP (called Authenticator), and a WPA-enabled client (called Supplicant).
802.1x ensures only authorized users can access the network. The 802.1x protocols supported by the Dell Wireless 4350 Small
Network Access Point are PEAP, TTLS & TLS.
In enterprises, WPA will be used in conjunction with both a wireless router and authentication server. In a Small Office/Home
Office (SOHO) environment, where there is no authentication server, users can use pre-shared key (PSK) mode in place of the
authentication server.
The Dell Wireless 4350 Small Network Access Point offers both WPA running in PSK mode and WPA with 802.1X authentication.
The mutual authentication and improved encryption technology of WPA allows wireless communication to achieve greater security.
Automatic Rate Selection and Rate Scaling
In 802.11g, wireless network adapters and access points can transmit data at one of the following rates: 54, 48, 36, 24, 18, 12, 9,
or 6 Mbps. In 802.11b, the data can be transmitted at a rate of 11, 5.5, 2, or 1 Mbps. As the distance between an adapter and
access point increases or decreases, the data rate automatically changes. Other factors, like interference, also affect the data rate.
The Dell Wireless 4350 Small Network Access Point uses automatic rate selection and rate scaling to determine the most efficient
rate of communication. Rate scaling maintains optimal communication between wireless clients and the WLAN.