Chapter 11 - Supplement - Sheet1 Flashcards
Benefits of layer 2 switching
Hardware-based bridging (ASIC), Wire speed, low latency, low cost
ASIC
Application-specific integrated circuits. Switches make decisions based on ASIC chips (hardware) instead of software, like how bridges operate
Limitations of Layer 2 Switching
Switches don’t break up broadcast domains, only collision domains
Three functions of layer 2 switching
Address learning, forward/filter decisions, loop avoidance
Address Learning
Switches build a forward/filter table of MAC addresses from the source field of packets sent to them.
Two version of the IEEE Spanning Tree Protocol
802.1D, 802.1w
5 problems that can affect data as it traverses network cable
Delay, Dropped Packets, Error, Jitter, Out-of-order delivery
Access Ports
Belongs to and carries the traffic of only one VLAN
Trunk Ports
Carries multiple VLANs at a time
Trunk Link
100Mbps or 1000Mbps point-to-point link between two switches, between a switch and a router, or between a switch and a server.
Max VLANS trunk links can carry traffic for
4094
Two VLAN identification methods
ISL, 802.1q
ISL
VLAN ID method. Inter-Switch Link - Encapsulates the data frame with its own header (that has a VLAN ID) and a CRC. Proprietary to Cisco. Fast Ethernet and Gigabit Ethernet only
IEEE 802.1Q
VLAN ID method. Inserts a field into the frame to ID the VLAN.
VTP
VLAN Trunking Protocol. Allows for management of VLANs throughout the network via a server or central switch
Default VTP mode for switches
VTP Server