Specifications
Table Of Contents
- AR Router Hardware Reference
- Copyright
- Contents
- Introduction
- Models Covered By This Reference
- Where To Find More Information
- Using Windows Terminal and Windows Hyperterminal
- Router Start-up
- Online Documentation
- AT-TFTP Server
- Memory
- AR300 Series Routers
- AR400 Series Routers
- AR700 Series Routers
- AT-RPS 740
- Mini Accelerator Cards (MACs)
- PCI Accelerator Cards (PACs)
- Flash Memory
- Interfaces
- Test Facility
- Cables And Loopback Plugs
- PICs and NSMs
- Restricted Procedures
- Contacting Us

Hardware Reference 59
C613-03058-00 REV A
Compression
MAC-based compression has the following features:
■
Local 32-bit processor for high speed control and data transfer.
■
Dedicated high performance 32-bit compression hardware.
■
High compression ratio Lempel-Ziv algorithm in hardware.
■
2 MBytes of history memory.
■
Support for up to 127 compression channels.
Compression and decompression operations are performed by a 32-bit data
compression coprocessor specifically designed for high-performance Lempel-
Ziv compression applications. The 2 MBytes of history memory allows up to
127 individual data links to use compression concurrently, enabling MACs to
provide compression for complicated network architectures. Figure 27 on page
59 shows typical compression ratios achieved by a MAC for a representative
set of file types.
Figure27: Typical hardware compression ratios by file type.
Encryption
MAC-based encryption has the following features:
■
Local 32-bit processor for high speed control and data transfer.
■
Dedicated high performance 32-bit Data Encryption Standard (DES)
hardware.
■
Optional key access control.
■
Support for up to 127 encryption channels.
MAC DES encryption is based on a fast 32-bit device that complies with FIPS
PUB 46, ISO DEA-1 and ANSI X3.92 standards.
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Font Program Window Text Object Spread
sheet
C source EPS Bitmap TIFF
File Type
Compression Ratio
CMPRATIO