32
Internetwork Packet Exchange
Internetwork Packet Exchange
103-000176-001
August 29, 2001
Novell Confidential
Manual
99a
38
July 17, 2001
Compression Slots
When you enable header compression, you can also specify the number of
compression slots. A compression slot is a location in router memory that
stores packet header information. The compression algorithm uses this
information to compress outgoing—and decompress incoming—packet
headers.
IMPORTANT:
You must allocate the same number of compression slots on each
router. If the values are different, the IPXWAN protocol chooses the lesser of the
two.
If too few compression slots are allocated for the number of different-style
packets crossing the connection, the values in the following IPXCON counters
become large:
Initialization Packets Sent
Initialization Packets Received
Uncompressed Packets Sent
Uncompressed Packets Received
The compression algorithm is running efficiently if the number of compressed
packets sent is significantly higher than the values in these counters.
A router sends an uncompressed packet when it is considered beneficial not to
reuse a compression slot.
Allocating too many compression slots has its own consequences. More
memory is required to store all the headers, and the compression algorithm
must scan through more stored headers to find a match for each transmitted
packet. This results in a higher processing load and slower performance.