Page 20 - Handout Computer Network.

• MANs also are used to interconnect several LANs by bridging them with backbone
lines.

Figure 2-3 shown a MAN Hierarchy

https://www.youtube.com/watch?v=o3wqv1lRnHg

2.4.4 Specialized Networks Located Within the LAN

There are times when smaller and more specialized networks might reside within the LAN.
Most notably, these specialized networks are used for access to storage systems, data center
technology systems and devices, intranets or extranets, and VPNs. These various specialized networks
are covered in this section.

https://www.youtube.com/watch?v=AlkqQUGPDc0

2.4.4.1 Storage-Area Networks (SANs)

A storage-area network (SAN) is a dedicated, high-performance network that moves data
between servers and storage resources. Because it is a separate dedicated network, it avoids any
traffic conflict between clients and servers, as shown in Figure 2-4.

• SAN technology allows high-speed server-to-storage, storage-to-storage, or serverto-
server connectivity. This method uses a separate network infrastructure that relieves any
problems associated with existing network connectivity. SANs offer the following features:
• Performance—SANs enable concurrent access to disk or tape arrays by two or more
servers at high speeds, providing enhanced system performance.
• Availability—SANs have disaster tolerance built in, because data can be mirrored using a
SAN up to 10 kilometers (km) (6.2 miles) away.
• Scalability—Like a LAN/WAN, a SAN can use a variety of technologies. This allows easy
relocation of backup data operations, file migration, and data replication between
systems.

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