Avaya P550 사용자 설명서
Overview of the P220 Gigabit Switch Family
Cajun P550/P220 Switch Operation Guide
2-7
Figure 2-3. Trunking Translation
Dual Layer Spanning Trees
Spanning trees are an IEEE 802.1 standard which provides distributed routing over
multiple LANs connected by bridges.
multiple LANs connected by bridges.
There are three spanning tree models:
❒ Single IEEE 802.1D spanning tree
❒ Spanning tree per VLAN
❒ Optimized “per-VLAN” spanning trees using a scalable, two-layer spanning tree
approach
Note: All models interoperate with legacy IEEE 802.1D bridges and switches.
Dual layer spanning trees provide two very important capabilities:
❒ Smaller spanning tree domains means much faster convergence during spanning
tree reconfiguration.
❒ Per-VLAN operation enables you to use more of the available bandwidth when you
have redundant links. A particular link can be blocked on one VLAN, but still
forward packets on another.
forward packets on another.
Frame
Format:
Format:
•“Clear”
•IEEE
802.1Q
•Multilayer
•3Com
•IEEE
802.1Q
•Multilayer
•3Com
T
rans
la
ti
on F
unc
ti
on
T
rans
la
ti
on F
unc
ti
on
Frame Format:
“Normal” - Ethernet
or 802.3 with valid
CRC
“Normal” - Ethernet
or 802.3 with valid
CRC
Trunking Translation:
Frame
Format:
Format:
•“Clear”
•IEEE
802.1Q
•Multilayer
•3Com
•IEEE
802.1Q
•Multilayer
•3Com