VLAN benefits

Posted by AJ × 08:49

• Traveling Users

– 20% to 40% of work force moves every year

• net admin’s biggest headache

• largest expense in managing networks. Moves may require...

– recabling

– readdressing and reconfiguration

– VLANs provide a way to control these costs. As long as the user still

belongs to the same VLAN...

• simply configure the new switch port to that VLAN

• router configuration remains intact

– Routers provide an effective firewall against broadcasts

– Adding VLANs can extend a router’s firewall capabilities to the “switch

fabric”

– The smaller the VLAN, the smaller the number of users that are effected

by broadcasts

– Shared LANs are easy to penetrate...simply plug into the shared hub.

– VLANs increase security by ...

• restricting number of users in a VLAN

• preventing user access without authorization

• configuring all unused ports to the “Disabled” setting

• control access by

– addresses

– application types

– protocol types

• Hub Replacement & Segmentation

– The ports on a non-intelligent hub can only be assigned one VLAN.

– Replacing hubs with switches is relatively cheap compared to the benefit

gained.

– In the graphic, replacing the core hub in an extended star topology with a

VLAN capable switch effectively microsegments one shared LAN into six.

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