Switches and LAN design requirements

LAN design requirements

Functionality:   the network must work

Scalability:   the network must be able to grow

Adaptability:   the network must be designed with a vision toward future technologies

Manageability:   the network should be designed to facilitate network monitoring and

management to ensure contiguous stability of operation

LAN design considerations

MDF:   Main distribution facility

IDF:   Intermediate distribution facility

HCC:  Horizontal cross-connect

VCC:  Vertical cross-connect

LAN design methodology

availability

measures the usefullnes of the network

things that affect availability

o       throughput

o       response time

o       access to resources

network designs should provide the greatest availability for the least cost

topology design

Network layer

Data link layer

Physical layer

VLANs

can be created for each workgroup

switches running VLANs

a router must be configured to allow routing between the VLANs

Hierarchical design model

access layer

provides users in workgroups access to the network

device used can be switch or hub

MAC layer filtering and microsegmentation

VLAN membership

distribution layer

provides policy-based connectivity

networks are segmented in BC domains

policies can be applied and ACLs can filter packets

VLAN routing

Switches in this layer operate at layer 2 and 3

Aggregation points for multiple access layer switches

core layer

provides optimal transport between sites

often referred to as the backbone

high-speed switching backbone

not perform any packet manipulation

redundant alternate paths stability