Ericsson HL950 Administrator's Manual page 152

Multi Service Edge Device HL950
Administrator's Guide
G.SHDSL
Also known as G.991.2, G.SHDSL is an international standard for symmetric DSL. G.SHDSL
provides for sending and receiving high-speed symmetrical data streams over a single pair of copper
wires at rates between 192 kbps and 2.31 Mbps. G.SHDSL was developed to incorporate the features
of other DSL technologies, such as ADSL and SDSL and will transport T1, E1, ISDN, ATM and IP
signals.
H
Hash Values
Locator numbers that replace a given value with a location in a table. The locator number is later used
to retrieve the original data. Hashing is analogous to storing a coat on a coat rack. The hash ID is
saved and used later for retrieval.
HTTP – HyperText Transfer Protocol
HTTP is the protocol that carries requests from a browser to a Web server and also transports Web
pages from a Web server back to the requesting browser. HTTP is the most universally used Web
transfer protocol, but it is not inherently a secure protocol.
I
IAD – Integrated Access Device
A device that multiplexes a variety of communications technologies in the customer's premises onto a
single telephone line for transmission to the carrier. It also demultiplexes the incoming stream into
their respective channels.
IAL – Integrated Access Line
ICMP – Internet Control Message Protocol
ICMP is an extension to the Internet Protocol (IP). ICMP supports packets containing error, control,
and informational messages. The PING command, for example, uses ICMP to test an Internet
connection.
ICMP Redirect
Not necessarily a malicious condition, some routers generate a redirection message whenever a packet
is rerouted. If these messages become excessive or if some mischievous person is generating these
messages in an exponential fashion this condition can become invasive.
IKE – Internet Key Exchange
IPBX – Integrated Private Branch eXchange
IPL – Integrated Private Line
IP Re-assembly
TCP/IP is a system of packet creation, packet disassembly, packet transmission, and packet re-
assembly. An intruder sometimes tries to intervene in the re-assembly process and insert bogus extra
or replacement segments.
IPSec – Internet Protocol Security
A method of providing secure communication over potentially insecure network components such as
intermediate routers. IPSec defines encryption, authentication, and key management standards. IPSec
protocols support two encryption modes: Transport and Tunnel. Transport mode encrypts only the data
portion (payload) of each packet, but leaves the header untouched. The more secure Tunnel mode
EN/LZT 108 5995 R3 Page 152 (159)
June 2003