Chapter 6: Static Port Trunks
100
Section I: Basic Operations
Load Distribution Methods
This section discusses the load distribution methods of static port trunks
and LACP port trunks, described in Chapter 7, “LACP Port Trunks” on
page 103.
When you create a static or LACP port trunk, you have to select a load
distribution method that controls how the switch is to distribute the traffic
load across the ports in the trunk. The AT-S63 Management Software
offers the following load distribution methods:
Source MAC Address (Layer 2)
Destination MAC Address (Layer 2)
Source MAC Address / Destination MAC Address (Layer 2)
Source IP Address (Layer 3)
Destination IP Address (Layer 3)
Source IP Address / Destination IP Address (Layer 3)
The load distribution methods examine the last three bits of a packet’s
MAC or IP address and compare the bits against mappings assigned to
the ports in the trunk. The port mapped to the matching bits is selected as
the transmission port for the packet.
In cases where you select a load distribution that employs either a source
or destination address but not both, only the last three bits of the
designated address are used in selecting a transmission port in a trunk. If
you select one of the two load distribution methods that employs both
source and destination addresses, port selection is achieved through an
XOR operation of the last three bits of both addresses.
As an example, assume you created a static or LACP aggregate trunk of
Ports 7 to 14 on a switch. The table below shows the mappings of the
switch ports to the possible values of the last three bits of a MAC or IP
address.
Assume you selected source MAC address as the load distribution
method and that the switch needed to transmit over the trunk a packet with
a source MAC address that ended in 9. The binary equivalent of 9 is 1001,
making the last three bits of the address 001. An examination of the table
above indicates that the switch would use Port 8 to transmit the frame
because that port is mapped to the matching bits.
Last 3 Bits
000
(0)
001
(1)
010
(2)
011
(3)
100
(4)
101
(5)
110
(6)
111
(7)
Trunk Ports
7
8
9
10
11
12
13
14
Summary of Contents for AT-S63
Page 14: ...Figures 14 ...
Page 18: ...Tables 18 ...
Page 28: ...28 Section I Basic Operations ...
Page 58: ...Chapter 1 Overview 58 ...
Page 76: ...Chapter 2 AT 9400Ts Stacks 76 Section I Basic Operations ...
Page 96: ...Chapter 5 MAC Address Table 96 Section I Basic Operations ...
Page 114: ...Chapter 8 Port Mirror 114 Section I Basic Operations ...
Page 116: ...116 Section II Advanced Operations ...
Page 146: ...Chapter 12 Access Control Lists 146 Section II Advanced Operations ...
Page 176: ...Chapter 14 Quality of Service 176 Section II Advanced Operations ...
Page 196: ...196 Section III Snooping Protocols ...
Page 204: ...Chapter 18 Multicast Listener Discovery Snooping 204 Section III Snooping Protocols ...
Page 216: ...Chapter 20 Ethernet Protection Switching Ring Snooping 216 Section III Snooping Protocols ...
Page 218: ...218 Section IV SNMPv3 ...
Page 234: ...234 Section V Spanning Tree Protocols ...
Page 268: ...268 Section VI Virtual LANs ...
Page 306: ...Chapter 27 Protected Ports VLANs 306 Section VI Virtual LANs ...
Page 320: ...320 Section VII Internet Protocol Routing ...
Page 360: ...Chapter 30 BOOTP Relay Agent 360 Section VII Routing ...
Page 370: ...Chapter 31 Virtual Router Redundancy Protocol 370 Section VII Routing ...
Page 372: ...372 Section VIII Port Security ...
Page 402: ...Chapter 33 802 1x Port based Network Access Control 402 Section VIII Port Security ...
Page 404: ...404 Section IX Management Security ...
Page 436: ...Chapter 36 PKI Certificates and SSL 436 Section IX Management Security ...
Page 454: ...Chapter 38 TACACS and RADIUS Protocols 454 Section IX Management Security ...
Page 462: ...Chapter 39 Management Access Control List 462 Section IX Management Security ...
Page 532: ...Appendix D MIB Objects 532 ...