Isdn Top-Up Bandwidth On Demand; Data Compression; Security On Isdn - Bay Networks Nautica 200 Reference Manual

ISDN Top-Up Bandwidth-On-Demand

Data Compression

Security on ISDN

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ISDN means that users can size their networks accurately without
worrying about peak demand operation. The Nautica router
automatically sets up one or more ISDN circuits to provide extra
bandwidth when the leased line or single-channel ISDN line
utilization exceeds configurable thresholds. Data is then shared
across all available links, allowing the ISDN calls to be cleared
automatically when demand decreases and so minimizing costs.
Some models in the Nautica Series have both ISDN and leased
line connections to allow users to test network utilization in real
time over ISDN before committing to leased circuits. As traffic
patterns change, leased circuits or ISDN can also be added or
removed at any site without making equipment redundant.
Data compression, based on an optional Lempel-Ziv algorithm,
gives typical compression ratios of between 2:1 and 8:1,
increasing the effective throughput to 512 Kb/s across a single
64 Kb/s ISDN link. This reduces ISDN call costs, and in
combination with Multilink can provide up to 2 Mb/s of
throughput between routers. Data compression is automatically
negotiated at link startup, depending on the parameters set at both
ends.
Security is important when using ISDN because it is a public
network. Bay Networks
designed to maintain security and prevent unauthorized access:
• Calling Line Identification (CLI or Caller ID) ensures that
incoming ISDN calling numbers are checked before access is
granted.
• Secure Unit is a mechanism that restricts automatic path
creation to other units and allows only previously defined
paths to be established.
Understanding the Technology
®
Nautica routers have several features
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