© 2006 Cisco Systems, Inc. All rights reserved. BCMSN v3.02-1 Defining VLANs Implementing Best Practices for VLAN Topologies. - презентация

1 © 2006 Cisco Systems, Inc. All rights reserved. BCMSN v Defining VLANs Implementing Best Practices for VLAN Topologies

2 © 2006 Cisco Systems, Inc. All rights reserved.BCMSN v Issues in a Poorly Designed Network Unbounded failure domains Large broadcast domains Large amount of unknown MAC unicast traffic Unbounded multicast traffic Management and support challenges Possible security vulnerabilities

3 © 2006 Cisco Systems, Inc. All rights reserved.BCMSN v Scalable Network Addressing Allocate IP address spaces in contiguous blocks. Allocate one IP subnet per VLAN. IT, Human Resources Sales, MarketingFinance, Accounting

4 © 2006 Cisco Systems, Inc. All rights reserved.BCMSN v Interconnection Technologies TechnologyUse Fast EthernetConnects end-user devices to the access layer switch Gigabit Ethernet Access to distribution switch, high-use servers 10-Gigabit Ethernet High-speed switch to switch links, backbones EtherChannelHigh-speed switch to switch links, backbones with redundancy

5 © 2006 Cisco Systems, Inc. All rights reserved.BCMSN v Determining Equipment and Cabling Needs Each link provides adequate bandwidth for traffic aggregating over that link.

6 © 2006 Cisco Systems, Inc. All rights reserved.BCMSN v VLANs and the Logical Network

7 © 2006 Cisco Systems, Inc. All rights reserved.BCMSN v Network Traffic Types Traffic types to consider: Network management IP telephony Multicast Normal data Scavenger class

8 © 2006 Cisco Systems, Inc. All rights reserved.BCMSN v Traffic Path for IP Telephony Consider complete traffic path when placing equipment and configuring VLANs.

9 © 2006 Cisco Systems, Inc. All rights reserved.BCMSN v Traffic Path for IP Multicast Consider complete traffic path when placing equipment and configuring VLANs.

10 © 2006 Cisco Systems, Inc. All rights reserved.BCMSN v Summary Poorly designed networks can lead to large broadcast domains. A hierarchical IP addressing scheme scales well in the Campus Infrastructure module. The interconnection technology used depends on the amount of traffic the link must carry. Select the best equipment, cabling, and interconnection technologies to connect devices. VLANs should map to the IP hierarchy for the Campus Infrastructure module. Separate voice and data VLANs are recommended.

11 © 2006 Cisco Systems, Inc. All rights reserved.BCMSN v