Enabling LLDP-MED:

LLDP-MED (Link Layer Discovery Protocol - Media Endpoint Discovery) is an extension of LLDP specifically for VoIP devices.

It allows network devices to advertise and receive configuration information, such as VLAN IDs, from the network switch.

Voice VLAN Feature:

The voice VLAN feature on switches is designed to simplify the deployment of VoIP by automatically placing voice traffic on a designated VLAN.

Configuring the appropriate access interfaces and VLAN ID for voice traffic ensures that voice packets are prioritized and properly segmented from other types of traffic.

Configuration Steps:

Enable LLDP-MED on the appropriate access interfaces:

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set protocols lldp-med interface ge-0/0/0

Enable the voice VLAN feature and specify the VLAN ID:

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set ethernet-switching-options voip interface ge-0/0/0 vlan voice

set ethernet-switching-options voip interface ge-0/0/0 forwarding-class assured-forwarding

References:

Juniper documentation on LLDP-MED

Juniper EX Series switch configuration guide for voice VLAN

From the provided IS-IS adjacency outputs:

R1 is configured to participate in both Level 1 and Level 2 (A): This is indicated by the adjacency states for both Level 1 and Level 2 on the R1 interfaces.

R2 is configured to participate in Level 2 only (D): This is shown by the adjacency state for Level 2 only on the R2 interfaces.

References:

The IS-IS adjacency outputs indicate the state and levels of participation for each router.

Configuration and command references from "Example configs for VMRCAXP01W.txt" and other documents provide context for understanding IS-IS states and levels​​​​​​.

A modified deficit round-robin (MDRR) scheduler is defined by the following three variables:

Priority (A):

Priority determines the importance of the queue, influencing the order in which packets are serviced. Higher priority queues are serviced before lower priority queues.

Transmit rate (C):

The transmit rate controls the amount of bandwidth allocated to each queue. It determines how quickly packets from a queue can be transmitted.

Buffer size (E):

Buffer size defines the amount of memory allocated to each queue for storing packets before they are transmitted. Larger buffer sizes can accommodate more packets but may introduce more latency.

References:

Detailed information on MDRR and its variables can be found in Juniper's QoS configuration guides and related networking documents​​​​.

To ensure proper functioning within an MST (Multiple Spanning Tree) region, the following parameters must match across all switches:

Revision number:

The revision number identifies the version of the MST configuration. All switches within the same MST region must have the same revision number to ensure consistency.

MSTI-to-VLAN mapping:

The MSTI (Multiple Spanning Tree Instance) to VLAN mapping must be identical on all switches. This mapping ensures that each VLAN is assigned to the correct spanning tree instance.

Configuration name:

The configuration name (or region name) must be the same across all switches. This name uniquely identifies the MST region and must be consistent to ensure switches recognize they are part of the same region.

References:

The MSTP configuration requirements are detailed in Juniper network configuration guides and standards documents on MSTP​​​​.

Based on the provided configuration, let's analyze each term to determine the correct forwarding class and acceptance of traffic:

Term 1:

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term 1 {

from {

protocol udp;

port [ 16000 16002 ];

}

then {

loss-priority high;

forwarding-class voice;

}

}

This term specifies that UDP traffic on ports 16000 and 16002 is assigned a high loss priority and placed in the "voice" forwarding class. The action does not include an explicit "accept;" statement, but traffic matching this term will be forwarded according to the specified forwarding class and priority.

Term 2:

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term 2 {

from {

protocol tcp;

port 4423;

}

then {

loss-priority low;

forwarding-class best-effort;

accept;

}

}

This term specifies that TCP traffic on port 4423 is assigned a low loss priority and placed in the "best-effort" forwarding class. It explicitly includes an "accept;" statement, meaning this traffic will be accepted and processed according to these parameters.

Term 3:

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term 3 {

from {

protocol tcp;

port [ 22 80 443 ];

}

then {

forwarding-class af;

}

}

This term specifies that TCP traffic on ports 22 (default SSH port), 80 (HTTP), and 443 (HTTPS) will be placed in the "af" forwarding class. There is no explicit "accept;" statement here, but the traffic matching this term will be forwarded according to the specified forwarding class.

Term 4:

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term 4 {

then {

forwarding-class best-effort;

accept;

}

}

This term applies to any traffic that does not match the previous terms. Such traffic will be placed in the "best-effort" forwarding class and explicitly accepted.

Statement A: "SSH traffic using the default port will be placed in the af forwarding class and accepted."

Correct. Term 3 matches TCP traffic on port 22 (default SSH port) and assigns it to the "af" forwarding class. Although "accept" is not explicitly stated, the traffic is forwarded based on this class.

Statement B: "SSH traffic using the default port will be placed in the best-effort forwarding class and accepted."

Incorrect. The default SSH port (22) matches Term 3, which places it in the "af" forwarding class, not "best-effort."

Statement C: "UDP traffic using the 16000 port will be placed in the voice forwarding class and accepted."

Correct. Term 1 matches UDP traffic on port 16000 and places it in the "voice" forwarding class. Although "accept" is not explicitly stated, the traffic is processed based on the forwarding class and priority.

Statement D: "UDP traffic using the 16000 port will be placed in the best-effort forwarding class and accepted."

Incorrect. UDP traffic on port 16000 matches Term 1, which places it in the "voice" forwarding class, not "best-effort."

Juniper Networks Configuration Guidelines and Command References

Detailed command references from the uploaded files, particularly those related to firewall and CoS configurations​​​​​​​​​​​​​​.

Analysis:References:

For Multiple Spanning Tree Protocol (MSTP) to operate correctly, all switches in the same region must have the same VLAN to instance mapping, revision level, and configuration name. These parameters ensure that all switches interpret the MSTP configuration consistently.

References:

MSTP Configuration Guide, Juniper Networks

Step 1: Identify the problem.

Devices do not support VPN NLRI, and you must prevent these devices from receiving BGP VPN routes.

Step 2: Analyze the possible solutions.

Option A: Configure an import policy on the remote peer to reject the routes when they are received.

This approach would require configuration on the remote peer, which might not always be practical or possible.

Option B: Configure an export policy on the local BGP peer to reject the VPN routes being sent to the remote peer.

This ensures the local BGP peer does not send the VPN routes to the remote peer, directly addressing the problem.

Option C: Configure a route reflector for the VPN NLRI.

This does not solve the issue of preventing the advertisement of VPN routes to non-supporting peers.

Option D: Configure the apply-vpn-export feature on the local BGP peer.

This feature ensures that the VPN export policies are applied, preventing the advertisement of VPN routes to peers that do not support VPN NLRI.

Step 3: Verify the configurations.

Option B and Option D directly address the requirement without needing configurations on the remote peer.

References:

Juniper BGP configuration guide on export policies​​​​​​.

Commands for applying export policies:

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set policy-options policy-statement term from protocol bgp-vpn

set policy-options policy-statement term then reject

set protocols bgp group export

set protocols bgp apply-vpn-export

Reviewing MST Configuration:

The configuration shown in the exhibit indicates MST (Multiple Spanning Tree) configuration for DS-1 and DS-2 switches.

For DS-1:

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mstp {

configuration-name Region-1;

revision-level 1;

interface ge-0/0/8;

interface ge-0/0/9;

interface ge-0/0/10;

interface ge-0/0/12;

msti 1 {

bridge-priority 4k;

vlan 10-19;

}

msti 2 {

bridge-priority 8k;

vlan 20-29;

}

}

For DS-2:

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mstp {

configuration-name Region-1;

revision-level 1;

interface ge-0/0/8;

interface ge-0/0/9;

interface ge-0/0/10;

interface ge-0/0/12;

msti 1 {

bridge-priority 8k;

vlan 10-19;

}

}

Understanding Bridge Priority:

In MSTP, the switch with the lowest bridge priority becomes the root bridge for the respective MST instance.

For MSTI 1:

DS-1 bridge-priority is 4k (4096)

DS-2 bridge-priority is 8k (8192)

Thus, DS-1 will be the root bridge for MSTI 1.

For MSTI 2:

DS-1 bridge-priority is 8k (8192)

DS-2 does not participate in MSTI 2.

Thus, DS-1 will be the root bridge for MSTI 2.

Analyzing VLAN Assignments:

DS-1 MSTI 1: VLANs 10-19, priority 4k

DS-1 MSTI 2: VLANs 20-29, priority 8k

DS-2 MSTI 1: VLANs 10-19, priority 8k

DS-2 does not have MSTI 2 configuration.

Conclusion:

DS-1 is the root bridge for MSTI 1 (C)

DS-2 does not participate in MSTI 2 (eliminates A)

DS-1 is the root bridge for MSTI 2 (D)

DS-2 is not the root bridge for MSTI 1 (eliminates B)

References:

Configuration snippets

Understanding of MSTP priorities and root bridge election