Reference Guide

Equal Cost Multi Paths is a routing algorithm that distributes network trac across multiple high-
bandwidth OSPF, BPG, IS-IS, and static routes to increase performance. The Extreme Networks
implementation supports multiple equal cost paths between points and divides trac evenly among
the available paths.
ESRP
Extreme Standby Router Protocol is an Extreme Networks-proprietary protocol that provides redundant
Layer 2 and routing services to users.
FDB
The switch maintains a database of all MAC address received on all of its ports and uses this information
to decide whether a frame should be forwarded or filtered. Each forwarding database (FDB) entry
consists of the MAC address of the sending device, an identifier for the port on which the frame was
received, and an identifier for the VLAN to which the device belongs. Frames destined for devices that
are not currently in the FDB are flooded to all members of the VLAN. For some types of entries, you
configure the time it takes for the specific entry to age out of the FDB.
FHSS
Frequency-Hopping Spread Spectrum is a transmission technology used in Local Area Wireless
Network (LAWN) transmissions where the data signal is modulated with a narrowband carrier signal
that 'hops' in a random but predictable sequence from frequency to frequency as a function of time
over a wide band of frequencies. This technique reduces interference. If synchronized properly, a single
logical channel is maintained. (Compare with DSSS (Direct-Sequence Spread Spectrum).)
HTTP
Hypertext Transfer Protocol is the set of rules for transferring files (text, graphic images, sound, video,
and other multimedia files) on the worldwide web. A web browser makes use of HTTP. HTTP is an
application protocol that runs on top of the TCP/IP suite of protocols. (RFC 2616: Hypertext Transfer
Protocol -- HTTP/1.1)
HTTPS
Hypertext Transfer Protocol over Secure Socket Layer, or HTTP over SSL, is a web protocol that encrypts
and decrypts user page requests as well as the pages that are returned by the web server. HTTPS uses
SSL as a sublayer under its regular HTTP application layering. (HTTPS uses port 443 instead of HTTP
port 80 in its interactions with the lower layer, TCP/IP.) SSL uses a 40-bit key size for the RC4 stream
encryption algorithm, which is considered an adequate degree of encryption for commercial exchange.
IBSS
An IBSS is the 802.11 term for an ad hoc network. See ad hoc mode.
ICMP
Internet Control Message Protocol is the part of the TCP/IP protocol that allows generation of error
messages, test packets, and operating messages. For example, the ping command allows you to send
ICMP echo messages to a remote IP device to test for connectivity. ICMP also supports traceroute,
which identifies intermediate hops between a given source and destination.
IGMP
Hosts use Internet Group Management Protocol to inform local routers of their membership in multicast
groups. Multicasting allows one computer on the Internet to send content to multiple other computers
Glossary
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