A. to provide service internetworking
B. to support transparency for Layer 2 frames
C. as a connection identifier to indicate destination
D. as a mapping to the DLCI in service internetworking
E. to provide a trunk by which all VLANs can navigate from one site to one or multiple sites

A. Layer 3 routing between the Access and Aggregation layers facilities the ability to span VLANsacross multiple access switches， which is a requirement for many server virtualization andclustering technologies.
B. “East-west” server-to-server traffic can travel between aggregation modules by way of the core，but backup and replication traffic typically remains within an aggregation module.
C. Load balancing， firewall service， and other network service are commonly integrated by the useof service modules that are inserted in the aggregation switched.
D. Virtualization tools allow a cost effective approach for redundancy in the network design byusing two or four VDCs from the same physical switch.

A. QoS ToS/DSCP values are required to be forwarded transparently
B. Device redundancy is required
C. Per-user ACL support is required
D. Multicast service support is required

A. The design supports multiple server subnets Cisco 642-874： Practice Exam
B. An end-user sees the IP address of the real server
C. SLB routes between the outside and inside subnets
D. The source or destination MAC address is rewritten， but the IP addresses left alone
E. SLB acts as a "bump in the wire" between servers and upstream firewall or Layer 3 devices

A. The bus is limited to 32 devices
B. It is a full duplex serial standard
C. It is a half-duplex serial standard
D. It allows up to 320 MB/s of shared channel bandwidth

A. IP address space is difficult to manage.
B. Broadcast and fault domains arc increased
C. Convergence time is fractionally slower than STP
D. Limits on clustering and NIC teaming are removed
E. Fast uplink convergence is supported tor failover and fallback

A. when the design implements Layer 2 between the access arid distribution blocks
B. when multiple vendor devices need to be supported
C. when preempt tuning of the default gateway is needed
D. when a robust method of backing up the default gateway is needed
E. when the design implements Layer 2 between the access switch and the distribution blocks
F. when the design implements Layer 2 between the access and distribution blocks

A. OSPF stub areas can be thought of as a simple form of summarization
B. OSPF cannot filter intra area routes
C. An ARR ran only exist in two areas - the backbone and one adjacent area
D. Performance issues in the Backbone area can be offset by allowing some traffic to transit anon-backbone area
E. the size of an area （the LSDB） will be constrained by the size of the IP MTU

A. Eliminate the management and support for redistribution by choosing and cutting over to asingle IGP at the time of merger
B. Maintain distinct pockets across a moving boundary of routing protocols， redistributing betweenthem
C. Manipulate the administrative distance of the different IGPs to be equal throughout the network
D. Leave the IGPs independent without redistribution wherever communication between companyentities is not required

A. core layer
B. Internet boundary
C. aggregation layer
D. aggregation and core layers
E. access and aggregation layers