Chapter 17
| General IP Routing
IP Routing and Switching
– 636 –
Figure 422: Virtual Interfaces and Layer 3 Routing
IP Routing and Switching
IP Switching (or packet forwarding) encompasses tasks required to forward packets
for both Layer 2 and Layer 3, as well as traditional routing. These functions include:
◆
Layer 2 forwarding (switching) based on the Layer 2 destination MAC address
◆
Layer 3 forwarding (routing):
■
Based on the Layer 3 destination address
■
Replacing destination/source MAC addresses for each hop
■
Incrementing the hop count
■
Decrementing the time-to-live
■
Verifying and recalculating the Layer 3 checksum
If the destination node is on the same subnetwork as the source network, then the
packet can be transmitted directly without the help of a router. However, if the MAC
address is not yet known to the switch, an Address Resolution Protocol (ARP)
packet with the destination IP address is broadcast to get the destination MAC
address from the destination node. The IP packet can then be sent directly with the
destination MAC address.
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Tagged or Untagged
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Summary of Contents for GTL-2881
Page 34: ...Section I Getting Started 34 ...
Page 48: ...Section II Web Configuration 48 Unicast Routing on page 651 ...
Page 151: ...Chapter 4 Interface Configuration VLAN Trunking 151 Figure 69 Configuring VLAN Trunking ...
Page 152: ...Chapter 4 Interface Configuration VLAN Trunking 152 ...
Page 230: ...Chapter 8 Congestion Control Automatic Traffic Control 230 ...
Page 596: ...Chapter 14 Multicast Filtering Multicast VLAN Registration for IPv6 596 ...
Page 620: ...Chapter 15 IP Configuration Setting the Switch s IP Address IP Version 6 620 ...
Page 672: ...Section III Appendices 672 ...
Page 678: ...Appendix A Software Specifications Management Information Bases 678 ...
Page 688: ...Appendix C License Statement GPL Code Statement Notification of Compliance 688 ...
Page 696: ...Glossary 696 ...
Page 706: ...GTL 2881 GTL 2882 E112016 ST R01 ...