Spanning Tree Protocol and RSTP Overview

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the consequence of turning off Spanning Tree Protocol (STP) in a switched network?

  • The network will operate with lower latency.
  • The network becomes unusable due to broadcast storms. (correct)
  • There will be enhanced security features.
  • The network will have a higher throughput.

What should be done first if a Spanning Tree failure occurs?

  • Reconfigure the entire network.
  • Increase the STP timers.
  • Manually remove redundant links. (correct)
  • Turn off all switches in the network.

What is the role of the stack master in a switch stack?

  • It controls switch operations and stores configuration files. (correct)
  • It handles all physical cable connections.
  • It manages the network clock.
  • It serves as a backup for all other switches.

How does a switch stack affect the STP diameter when adding more switches?

<p>The STP diameter reduces with a properly managed switch stack. (A)</p> Signup and view all the answers

What is the recommended maximum diameter for switches using default STP timers?

<p>7 switches (D)</p> Signup and view all the answers

What is assigned to the switch stack as a whole in the network?

<p>One IP address (C)</p> Signup and view all the answers

What is the forwarding delay timer's default setting in the Spanning Tree Protocol?

<p>15 seconds (D)</p> Signup and view all the answers

In terms of stack member priority, what determines which switch becomes the stack master?

<p>The highest stack member priority value (B)</p> Signup and view all the answers

What is the primary benefit of Rapid PVST+ over standard Spanning Tree Protocol (STP)?

<p>It allows for multiple instance processing per VLAN. (A)</p> Signup and view all the answers

Which feature is NOT compatible with switches running RSTP?

<p>BackboneFast (A), UplinkFast (D)</p> Signup and view all the answers

How does RSTP signify a lost connectivity in its operation?

<p>By detecting an absence of 3 consecutive BPDUs. (D)</p> Signup and view all the answers

What is the defining characteristic of an edge port in RSTP?

<p>Immediately transitions to the forwarding state. (B)</p> Signup and view all the answers

What type of port connection does RSTP define as Point-to-Point?

<p>A full-duplex connection between two switches. (B)</p> Signup and view all the answers

Which of the following statements about RSTP BPDUs is true?

<p>Type 2, version 2 BPDUs are utilized. (C)</p> Signup and view all the answers

What is an essential function of the spanning-tree portfast command?

<p>It allows a port to transition immediately to forwarding. (A)</p> Signup and view all the answers

What happens if RSTP detects a shared link type?

<p>It configures the port in half-duplex mode. (C)</p> Signup and view all the answers

What is the protocol version set to in an 802.1D BPDU frame?

<p>0 (A)</p> Signup and view all the answers

Which bit in the BPDU frame indicates a topology change?

<p>Flags bit (D)</p> Signup and view all the answers

During STP operation, what happens when a switch is powered on?

<p>It assumes it is the root bridge until BPDUs are sent. (B)</p> Signup and view all the answers

What does an STP switch do with a BPDU from another switch that has a higher Bridge ID?

<p>Ignores the information from that switch. (B)</p> Signup and view all the answers

What is the purpose of the 'Max age' field in a BPDU?

<p>Decides how long the current configuration message will be retained. (A)</p> Signup and view all the answers

What does a switch do after it has updated its root ID based on a received BPDU?

<p>Sends out BPDUs on all ports to indicate the new root. (C)</p> Signup and view all the answers

What is the role of the 'Hello time' in STP?

<p>Indicates the time interval between each BPDU sent on a port. (A)</p> Signup and view all the answers

Which piece of information does the 'Root path cost' field convey in a BPDU?

<p>The aggregated cost to reach the root bridge. (D)</p> Signup and view all the answers

Flashcards

Spanning Tree Protocol (STP)

A network protocol that prevents loops in switched networks by blocking redundant links.

STP Failure Consequences

Disrupts network operation and may render the switched network unusable due to a lack of Layer 2 time-to-live (TTL).

Repairing STP Problems

Involves manually removing redundant links, identifying and resolving the root cause of failure, and isolating problems by re-enabling/reinstalling cables.

Switch Stacking

Connecting multiple switches to operate as a single logical unit.

Signup and view all the flashcards

Stack Master

The switch that controls the operation of a switch stack, assigned one IP address to represent the stack.

Signup and view all the flashcards

Switch Stack Diameter

The maximum number of switches through which data must pass to connect two switches in a stack.

Signup and view all the flashcards

Stack Member Priority

A value configured on each switch in a stack to determine which switch becomes the stack master. Higher value is master

Signup and view all the flashcards

STP and Stack Relationship

A single spanning tree instance is created for each stack of switches to ensure that the total number of switches does not affect the diameter of the spanning tree.

Signup and view all the flashcards

802.1D BPDU Frame

A protocol used by switches to determine the root bridge in a spanning tree.

Signup and view all the flashcards

Root Bridge

The central switch in a spanning tree network.

Signup and view all the flashcards

BPDU Propagation

The process where switches exchange BPDUs to discover and select the root bridge.

Signup and view all the flashcards

Bridge ID (BID)

A unique identifier for each switch, used in STP calculations to determine the root bridge.

Signup and view all the flashcards

Root ID

The bridge ID of the root bridge.

Signup and view all the flashcards

STP Process

An algorithm that prevents loops and redundancy in a switched network.

Signup and view all the flashcards

Topology Change

Indicates a change in the network's topology.

Signup and view all the flashcards

Port ID

The identifier for a port on a switch, used in BPDU propagation.

Signup and view all the flashcards

Rapid PVST+

A Cisco version of Rapid Spanning Tree Protocol (RSTP) that speeds up STP recalculations for faster convergence.

Signup and view all the flashcards

Alternate Port

A port in Rapid PVST+ that is designated as a backup path in case the primary path fails.

Signup and view all the flashcards

Backup Port

A port in Rapid PVST+ that is a secondary path.

Signup and view all the flashcards

RSTP BPDUs

Bridge Protocol Data Units of type 2, version 2 used in RSTP for communication and keep-alive between switches.

Signup and view all the flashcards

Edge Port

A port directly connected to a device (not another switch) and immediately goes to the forwarding state in spanning tree protocols.

Signup and view all the flashcards

Point-to-Point Link

A full-duplex link connecting one switch/device to another.

Signup and view all the flashcards

Shared Link

A half-duplex link, often connecting a switch to a hub.

Signup and view all the flashcards

Spanning Tree PortFast

A Cisco command to immediately place a port into the forwarding state.

Signup and view all the flashcards

Study Notes

ICMPv6 Neighbor Discovery

  • ICMPv6 Neighbor Discovery defines five different packet types
  • Router Solicitation Message, used with dynamic address allocation
  • Router Advertisement Message, used with dynamic address allocation
  • Neighbor Solicitation Message, used with address resolution (IPv4 ARP)
  • Neighbor Advertisement Message, used with address resolution (IPv4 ARP)
  • Redirect Message, similar to ICMPv4 redirect messages (Router-to-Device messaging)

Dynamic Address Allocation in IPv4

  • Dynamic addressing in IPv4 uses DHCPv4 server
  • A device requests an IP address from the server
  • The server assigns an address to the device

Dynamic Address Allocation in IPv6

  • Dynamic addressing in IPv6 uses ICMPv6 Router Solicitation and ICMPv6 Router Advertisement
  • SLAAC, Stateless DHCPv6, Stateful DHCPv6 are used for allocation.

RA Message Options

  • ICMPv6 Router Advertisement Option 1, 2, or 3
  • Other Configuration ("O") Flag
  • Managed Configuration ("M") Flag
  • Configuring Flags discussed in Lesson 8

Option 3 and the "A" Flag

  • ICMPv6 RA, M Flag = 1, A Flag = 0
  • Autonomous address configuration (A) flag tells hosts they can create an address for themselves by combining the prefix in the RA with an interface identifier
  • Configuring Flags discussed in Lesson 8

Router Solicitation/Router Advertisement

  • Router Solicitation is sent when a device needs IPv6 addressing information
  • Router Advertisement is sent every 200 seconds or in response to RS.

Analyzing the Router Solicitation Message

  • To: FF02::2 (All-IPv6 Routers)
  • From: FE80::50A5:8A35:A5BB:66E1
  • ICMPv6 Router Solicitation

Analyzing the Router Advertisement Message

  • To: FF02::1 (All-IPv6 devices)
  • From: FE80::1 (Link-local address)
  • ICMPv6 Router Advertisement

Neighbor Solicitation and Neighbor Advertisement

  • NS: Multicast, NS: Solicited Node Multicast, Ethernet
  • NA: Unicast, NA: Unicast, IPv6 Header, ICMPv6: Neighbor Solicitation/Advertisement

ICMPv6 Redirect

  • Similar functionality to ICMPv4
  • A router informs an originating host of the closer IP address of a router.
  • Unlike IPv4, a router informs an originating host that the destination host is on the same link.

ICMPv6 Duplicate Address Detection (DAD)

  • Duplicate Address Detection (DAD) is used to confirm unique IPv6 unicast addresses on a link.
  • A device sends a Neighbor Solicitation for its own unicast address
  • If no Neighbor Advertisement is received, the address is deemed unique
  • Once required, RFC updated to recommend /64 interface ID for uniqueness.

Neighbor Cache

  • Neighbor Cache maps IPv6 addresses to Ethernet MAC addresses
  • Similar to ARP Cache for IPv4
  • 5 states: Reachable, Stale, Incomplete, Delay, Probe

VLSM and CIDR

  • Prior to 1981, IP addresses used the first 8 bits to specify the network portion of the address.
  • In 1981, RFC 791 modified the IPv4 address to allow for three different classes.
  • IP address space was depleting rapidly.
  • The IETF introduced Classless Inter-Domain Routing (CIDR).
  • CIDR uses Variable Length Subnet Masking (VLSM) to help conserve address space.
  • VLSM is a way of subnetting a subnet.

Classful and Classless IP Addressing

  • Classful IP addressing is based on the first octet
  • Initiatives to conserve IPv4 address space include: VLSM & CIDR notation, Network Address Translation, and Private Addressing
  • Classful addresses are identified by the decimal number of the 1st octet (Class A, B, C)
  • The IPv4 Classful Addressing Structure (RFC 790) had the network and host portions
  • Subnet mask is used to determine network and host portion of an IP address.
  • Classful routing protocols (like RIPV1) did not send subnet masks.
  • Classless Inter-domain Routing (CIDR) improves efficiency and requires subnet masks in routing updates

STP

  • Build a simple switched network with redundant links
  • Explain common problems in a redundant, switched network.
  • Build a simple switched network using STP.
  • Describe different spanning tree varieties
  • Explain PVST+ and Rapid PVST+

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

ICMPv6 Neighbor Discovery PDF

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser