Chapter 4: Basic Concepts and Management
Next, the switch assigns an IP address to each VLAN. Usually, we use 10.x.x.x as the internal IP block. Because there are a total of four VLANs in the network, we must assign four IP blocks to each of them.
Table
each VLAN.
Name | VID | Network Address |
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Marketing | 2 | 10.1.2.0/24 |
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Service | 3 | 10.1.3.0/24 |
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Sales | 4 | 10.1.4.0/24 |
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Administration | 1 | 10.1.1.0/24 |
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Here we apply the subnet mask 255.255.255, and each VLAN can support 254 nodes.
4.7 Link Aggregation (LGB2118A Only)
Link Aggregation combines the bandwidth of more than one port to an assigned logical link. This increases total bandwidth to the targeted device. There is more than one Link Aggregation technology in many vendors’ switch products already, which may cause an interoperability problem. 802.3ad Link Aggregation Control Protocol (LACP) can solve this problem.
Why 802.3ad (LACP)?
Networks vary. For example, if a port malfunctioned or is unplugged accidentally in a static trunk port, the administrator has to reconfigure it, or the network will have problems. The administrator needs a tool with automatic recovery capability. LACP is a protocol that allows a switch to know whether its partner has the capability to setup a trunk between them.
Usually, if the administrator wishes to increase the bandwidth of a specific link, he may:
1.Buy new network equipment with higher throughput, or
2.Aggregate the bandwidth of more than one port to a logical link.
In case 1, you will pay much more money, and hardware performance may limit the solution’s scalability.
In case 2, you save money, because all equipment is there already. You can also the solve the interoperability issue. Applying LACP in your network, you will not only gain the benefits listed below to improve the performance of your network but also have these investments to use for future new products.
1.Public standardized specification.
2.No interoperability issues.
3.No change to IEEE 802.3 frame format; no change in software and management.
4.Increased bandwidth and availability.
5.Load sharing and redundancy.
6.Automatic configuration.
7.Rapid configuration and reconfiguration.
8.Deterministic behavior.
9.Low risk of duplication or
10.Support existing IEEE 802.3 MAC Clients.
11.Backward compatibility with
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