48 AR700 Series Router
C613-03087-00 Rev E
Compression PAC-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 PACs to
provide compression for complicated network architectures. Figure20 shows
typical compression ratios achieved by a PAC for a representative set of file
types.
Figure 20: Typical hardware compression ratios by file type
Encryption PAC-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 and
Triple DES (3DES) – hardware.
PAC DES and triple DES encryption are based on a fast 32-bit device that
complies with FIPS PUB 46, ISO DEA-1 and ANSI X3.92 standards.
Dual Mode Throughput of an encrypted link can be dramatically increased by using data
compression. To support this, ECPACs support both encryption and
compression, providing a dual mode that allows combined compression and
encryption operations. So that the compression phase will have the best
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File Type
Compression Ratio
CMPRATIO