6
C
ONFIGURING
AND
M
ANAGING
IP
I
NTERFACES
AND
S
ERVICES
This chapter describes how to configure IP interfaces and services.
MTU Support
Mobility System Software (MSS) supports standard maximum
transmission units (MTUs) of 1514 bytes for standard Ethernet packets
and 1518 bytes for Ethernet packets with an 802.1Q tag. MSS does not
support changing of the MTU through software configuration, and MSS
does not do path MTU discovery.
Communication between WX switches is supported over any path MTU,
and the Mobility Domain itself can run over the minimum IP path MTU
(PMTU). However, tunnels between two WX switches require a path MTU
of at least 1384 bytes.
This minimum MTU path is required because MSS uses IP tunnels to
transport user traffic between WX switches and to transport user traffic
and control traffic between switches and MAPs. Encapsulation of the
packets for tunneling adds an additional 44 bytes to the packet headers,
so MSS does fragment and reassemble the packets if necessary to fit
within the supported MTUs. However, MSS does not support
defragmentation except at the receiving end of an IP tunnel, and only to
reassemble fragments created by another WX switch device for
tunneling.
If the path MTU between WX switches is less than 1384 bytes, a device in
the path might further fragment or drop a tunneled packet. If the packet
is further fragmented, the receiving WX switch will not be able to
reassemble the fragments, and the packet is dropped.
Summary of Contents for 3CRWX120695A
Page 138: ...138 CHAPTER 6 CONFIGURING AND MANAGING IP INTERFACES AND SERVICES ...
Page 272: ...272 CHAPTER 11 CONFIGURING RF LOAD BALANCING FOR MAPS ...
Page 310: ...310 CHAPTER 13 CONFIGURING USER ENCRYPTION ...
Page 322: ...322 CHAPTER 14 CONFIGURING RF AUTO TUNING ...
Page 350: ...350 CHAPTER 16 CONFIGURING QUALITY OF SERVICE ...
Page 368: ...368 CHAPTER 17 CONFIGURING AND MANAGING SPANNING TREE PROTOCOL ...
Page 412: ...412 CHAPTER 19 CONFIGURING AND MANAGING SECURITY ACLS ...
Page 518: ...518 CHAPTER 21 CONFIGURING AAA FOR NETWORK USERS ...
Page 530: ...530 CHAPTER 22 CONFIGURING COMMUNICATION WITH RADIUS ...
Page 542: ...542 CHAPTER 23 MANAGING 802 1X ON THE WX SWITCH ...
Page 598: ...598 CHAPTER 26 ROGUE DETECTION AND COUNTERMEASURES ...
Page 706: ...706 GLOSSARY ...