Cabletron Systems HSIM-W6 Installation Manual

Also see for CyberSWITCH HSIM-W6: Setup guide Configuration guide User guide User guide

Contents

HSIM-W6 Firmware SupportHSIM-W6 Installation Guide2-9The ANSI standard defines a mechanism for the network to signal the existence of congestion,called Explicit Congestion Notification (ECN) bits. Frame Relay uses FECN (Forward ECN) andBECN (Backward ECN) bits to notify end user devices about network congestion. Although theFrame Relay protocol does not respond to congestion, some higher layer protocols for end userdevices may respond to ECNs by recognizing that delays have increased, or that frames have beendropped.Point-to-Point ProtocolPPP is a data link layer industry standard WAN protocol for transferring multi-protocol data trafficover point-to-point connections. It is suitable for both high-speed synchronous ports as well aslower speed asynchronous dial-up ports. With this protocol, options such as security and networkprotocols can be negotiated over the connection.This device supports synchronous PPP over the ISDN port. In Single Link Mode, PPP uses oneISDN B channel for data transmission. PPP runs over each ISDN B channel for two separateconversations (split B-channel). In Multi-Link Protocol Mode, PPP simultaneously sends andreceives data over two ISDN B-channels on the same connection to optimize bandwidth usage.The STAC Electronics Stacker LZS Compression Protocol is supported over PPP providing up to4:1 data compression.PAP and CHAP SecurityThe HSIM-W6 supports the Password Authentication Protocol (PAP) and Challenge HandshakeAuthentication Protocol (CHAP) under PPP.PAP provides verification of passwords between devices using a 2-way handshake. One device(peer) sends the system name and password to the other device (authenticator). Then theauthenticator checks the peer’s password against the configured remote peer’s password andreturns acknowledgment.CHAP is more secure than PAP as unencrypted passwords are not sent across the network. CHAPuses a 3-way handshake and supports full or half-duplex operation.