Layer 3 Marking IP Precedence DSCP

- Three most significant bits of ToS byte are called IP precedence. - Other bits are unused. DiffServ - Six most significant bits of ToS byte are called DiffServ Code Point (DSCP). - DSCP is backward compatible with IP precedence. - Remaining two bits are used for flow control. QoS Layer 3 classification results from the examination of header values such as destination IP address or protocol. QoS Layer 3 marking occurs in the Type of Service (ToS) byte in the IP header. The first three bits of...

Describing Port Security

This topic describes how port security is used to block input from devices based upon Layer 2 restrictions. Port security restricts port access by MAC address. Port security is a feature supported on Cisco Catalyst switches that restricts a switch port to a specific set or number of MAC addresses. Those addresses can be learned dynamically or configured statically. The port will then provide access to frames from only those addresses. If, however, the number of addresses is limited to four but...

Layer 2 Marking 8021p CoS

3 bits used for CoS (802.1p user priority) 3 bits used for CoS (802.1p user priority) 802.1p User Priority field is also called class of service (CoS). Different types of traffic are assigned different CoS values. CoS 6 and 7 are reserved for network use. QoS Layer 2 classification occurs by examining information in the Ethernet or 802.1Q header, such as destination MAC address or VLAN ID. QoS Layer 2 marking occurs in the Priority field of the 802.1Q header. LAN Layer 2 headers have no means...

Module Self Check

Use the questions here to review what you learned in this module. The correct answers and solutions are found in the Module Self-Check Answer Key. Q1) What are two similarities between WLANs and wired LANs (Choose two.) (Source Introducing WLANs) B) Both use the same frame format. C) Both can run the same applications. D) Both use the same physical layer. Q2) What are two differences between WLANs and wired LANs (Choose two.) (Source Introducing WLANs) A) WLAN uses CSMA CA and wired LAN uses...

WLAN Controller Web Menu

This subtopic describes the menu bar of the WLAN controller web interface. configurations, such as SSIDs and security policies for all user groups WIRELESS Provides access point configurations, clients management, and various RF settings MANAGEMENT Provides integration into the network, such as IP addressing and SNMP MONITOR WLANs CONTROLLER WIRELESS SECURITY MANAGEMENT COMMANDS HELP MONITOR Provides a view of this controller, its access points, and wireless clients CONTROLLER Provides...

QoS and Voice Traffic in the Campus Model

Any of the above scenarios could result Delay-sensitive applications like voice need QoS. Regardless of the speed of individual switches or links, speed mismatches, many-to-one switching fabrics, and aggregation may cause a device to experience congestion, which can result in latency. If congestion occurs and congestion management features are not in place, then some packets will be dropped, causing retransmissions that inevitably increase overall network load. QoS can mitigate latency caused...

Applies the VLAN access map to the specified VLANs

VACLs (also called VLAN access maps in Cisco IOS software) apply to all traffic on the VLAN. You can configure VACLs for IP, and MAC-layer traffic. VACLs follow route-map conventions, in which map sequences are checked in order. When a matching permit ACE is encountered, the switch takes the action. When a matching deny ACE is encountered, the switch checks the next ACL in the sequence or checks the next sequence. Permit (with capture, Catalyst 6500 only) Redirect (Catalyst 6500 only) Deny...

Attacks on switch devices

Significant attacks in these categories, known as of this writing, are discussed in more detail in subsequent sections of the course. Each attack method is accompanied by a standard measure for mitigating the security compromise. Building Cisco Multilayer Switched Networks (BCMSN) v3.0 Switch Security Concerns and Mitigation Steps The table describes attack methods and the steps to mitigation. The table describes attack methods and the steps to mitigation. Frames with unique, invalid source MAC...

UNII3 band currently not allowed in most of Europe

To use the 11 new channels, radios must comply with two features that are part of the 802.11h specification Transmit Power Control (TPC) and Dynamic Frequency Selection (DFS). DFS dynamically instructs a transmitter to switch to another channel whenever a particular condition (such as the presence of a radar signal) is met. Prior to transmitting, the DFS mechanism of a device monitors its available operating spectrum, listening for a radar signal. If a signal is detected, the channel associated...