ECP-206 Exam Dumps - Ericsson Certified Associate - IP Networking

The maximum number of unique VLAN IDs available is 4096. A VLAN ID is a 12-bit identifier that can range from 0 to 4095. However, VLAN ID 0 is reserved for tagging the priority of frames and VLAN ID 4095 is reserved for implementation use, so only VLAN IDs from 1 to 4094 are available for user configuration78. VLAN IDs are used to identify different broadcast domains or subnets on a Layer 2 network. VLAN IDs are carried in the IEEE 802.1Q tag in the Ethernet frame header.

References: What is a virtual LAN (VLAN) and how does it work with my managed switch? - NETGEAR Support, Virtual LANs (VLANs) - Cisco

The command that is used to begin making changes to the router settings in an Ericsson Router 6000 is configure. This command enters the configuration mode, where various commands can be used to modify the router parameters, such as interfaces, protocols, services, security, etc. To exit the configuration mode, the command end can be used. To save the changes made in the configuration mode, the command commit can be used56.

References: Router 6000 Series - Ericsson, Ericsson Router 6000 series (6471/6672/6675) Commands for 2G/3G/4G/5G technologies… - YouTube

Referring to the exhibit, the two Ericsson routers that support the 100GE interface are Router 6675 and Router 6672. The 100GE interface is a high-speed Ethernet interface that operates at 100 gigabits per second. The Ericsson Router 6000 series is a family ofrouters that provide IP transport for mobile and fixed networks. The Router 6675 is a 5G combined access and E-RAN switch with 100GE interfaces and 320Gb forwarding capacity. The Router 6672 is a high-capacity metro aggregation router with 100GE interfaces and 1.6Tb forwarding capacity12.

References: Router 6000 Series - Ericsson, New Ericsson Router 6000 series couples radio and IP transport for 5G future - Global Brands Magazine

A network operator who wants to make sure voice data is prioritized should assign it to Ethernet traffic class 6. Ethernet traffic class is a term used to refer to the priority code point (PCP) field in the VLAN header of an Ethernet frame. The PCP field is a 3-bit field that can encode up to eight different priority levels, ranging from 0 (lowest) to 7 (highest). The PCP values can be mapped to different types of traffic according to their QoS requirements. The recommended mapping is as follows :

• PCP 0: Best effort (default)
• PCP 1: Background
• PCP 2: Spare
• PCP 3: Excellent effort
• PCP 4: Controlled load
• PCP 5: Video
• PCP 6: Voice
• PCP 7: Network control

Voice data is a type of real-time traffic that requires the highest priority and lowest delay in the network. Therefore, it should be assigned to PCP 6, which corresponds to Ethernet traffic class 6 .

References: [IEEE 802.1Q - Wikipedia], [What is “link aggregation” and how does it benefit your network? | PC Gamer]

 IPv6 link-local addresses are designed to be used in three situations: for neighbor discovery, for local IP communication on the IPv6 capable routers, and for addressing on a single link for purposes such as auto-address configuration. Neighbor discovery is a protocol that allows IPv6 nodes to discover each other and learn their link-layer addresses on a local network. Neighbor discovery uses link-local addresses to send and receive messages such as router advertisements, router solicitations, neighbor advertisements, and neighbor solicitations34. Local IP communication on the IPv6 capable routers refers to the ability of routers to exchange routing information or management traffic using their link-local addresses as source and destination addresses. This reduces the need for global unicast addresses on router interfaces that are not reachable from outside the local network35. Addressing on a single link for purposes such as auto-address configuration refers to the use of link-local addresses to enable IPv6 nodes to obtain an address without manual configuration or a DHCP server. Link-local addresses can be automatically derived from the interface identifier in the modified EUI-64 format or randomly generated. Link-local addresses can also be used to test the connectivity of a link before obtaining a global unicast address36.

References: Understand the IPv6 Link-Local Address - Cisco, Link Local Address - GeeksforGeeks, IPv6 Address Types | Link-Local, Global Unicast, etc.⋆ IPCisco, MPLS Label Distribution Protocol Commands - Cisco

Two statements that are correct for LDP are:

• LSRs send UDP hello messages for neighbor discovery. LDP is a protocol that distributes labels for MPLS forwarding along the shortest path calculated by an IGP. LDP uses two types of messages: discovery messages and session messages. Discovery messages are used to discover and maintain adjacency with other LSRs that support LDP. Discovery messages are sent as UDP datagrams to the well-known multicast address 224.0.0.2 (all routers on this subnet) on port 64634.
• LSRs use TCP to negotiate LDP session parameters. Session messages are used to establish, maintain, and terminate LDP sessions between LSRs. Session messages are also used to exchange label mappings, notification messages, and keepalive messages. Session messages are sent as TCP segments to port 64634.

References: Ldp | Microsoft Learn, Label Distribution Protocol - Wikipedia

The protocol that would be used to bundle multiple Ethernet ports into a virtual link with an aggregated bandwidth is LACP, which stands for Link Aggregation Control Protocol. LACP is a protocol that allows two or more devices to negotiate the formation of a link aggregation group (LAG), also known as an EtherChannel or a port channel. A LAG combines multiple physical links into one logical link that provides increased bandwidth, load balancing, and redundancy. LACP is defined in IEEE 802.3ad and 802.1AX standards12.

References: Link Aggregation Control Protocol - Wikipedia, What is “link aggregation” and how does it benefit your network? | PC Gamer

The code that is commonly used to assign higher priority to VoIP traffic is EF, which stands for Expedited Forwarding. EF is a per-hop behavior (PHB) defined by the Differentiated Services (DiffServ) model for QoS. EF provides low delay, low jitter, and low loss for real-time applications such as VoIP. EF is marked by setting the DSCP value to 101110, which corresponds to decimal 4678. AF31, which stands for Assured Forwarding class 3 low drop probability, is another PHB defined by DiffServ, but it provides lower priority than EF. AF31 is marked by setting the DSCP value to 011010, which corresponds to decimal 2678. DF, which stands for Default Forwarding, is a PHB defined by DiffServ that provides best-effort service for unmarked traffic. DF is marked by setting the DSCP value to 000000, which corresponds to decimal 078. AF11, which stands for Assured Forwarding class 1 low drop probability, is another PHB defined by DiffServ, but it provides lower priority than EF and AF31. AF11 is marked by setting the DSCP value to 001010, which corresponds to decimal 1078.

References: Differentiated services - Wikipedia, Solved: Cisco VoIP Phone traffic marking - Cisco Community

OSPF runs directly on IP, while IS-IS runs directly on Ethernet. This means that OSPF uses IP addresses to identify routers and links, while IS-IS uses MAC addresses or other link-layer identifiers. OSPF also requires an IP header for each packet, while IS-IS does not. Both OSPF and IS-IS are link state protocols, which means that they flood information about the network topology to all routers in the same area or domain. References: Ericsson IP Networking - Routing Protocols, Ericsson Router 6000 Series - Ericsson

The conceptual table created by routing protocols that is used when processing an IP packet is the forwarding information base (FIB). The FIB is a table that contains the bestroutes to reach each destination network prefix, along with the outgoing interface and the next-hop address for each route. The FIB is derived from the routing information base (RIB), which is a table that contains all the routes learned from different routing protocols and sources. The FIB is used by the router to make fast forwarding decisions for each incoming packet, based on its destination address12.

References: Security Hardening Checklist Guide for Cisco Routers/Switches in 10 Steps, VLAN - Wikipedia

The Area ID to which the router belongs is 49.00F0.0100. The Area ID is a variable-length field in the NSAP address that identifies the area to which the router belongs. The Area ID can be between 1 and 13 bytes long, but it must start and end with an octet (8 bits). The NSAP address is composed of three parts: the authority and format identifier (AFI), the area ID, and the system ID. The AFI is a one-octet field that indicates the format and authority of the rest of the address. The system ID is a fixed-length field of six octets that uniquely identifies the router within an area. The NSAP address also has a network selector (NSEL) field, which is a one-octet field that identifies the network layer service to which a packet should be sent. For IS-IS routers, the NSEL must always be 00.

In this question, the NSAP address is 49.00F0.0100.5012.3010.00. This means that:

• The AFI is 49, which indicates a private address.
• The Area ID is 00F0.0100, which is four octets long and starts and ends with an octet.
• The system ID is 5012.3010, which is six octets long and identifies the router within the area.
• The NSEL is 00, which indicates IS-IS.

Therefore, the answer is B.

References: Ericsson IP Networking - Routing Protocols, IS-IS NSAP address - Cisco Community, Understanding IS-IS NSAP Addresses - Todd Lammle, LLC, IS-IS - Nokia, Network service access point address - Wikipedia

IPsec provides two main features: protecting packets from modification and hiding the content of packets from observation. IPsec protects packets from modification by using cryptographic algorithms to generate and verify message authentication codes (MACs) or digital signatures for each packet. These mechanisms ensure that the packets have not been tampered with or altered in transit by unauthorized parties. IPsec hides the content of packets from observation by using encryption algorithms to scramble the payload of each packet. This prevents eavesdroppers or interceptors from reading or analyzing the data carried by the packets12.

References: What is IPsec? | How IPsec VPNs work | Cloudflare, IPsec - Wikipedia

To differentiate traffic types for the purpose of prioritization in their Ethernet LAN and IP/MPLS backbone, an operator can use the following three fields:

• Traffic Class (TC): This is a 3-bit field in the MPLS label that can be used to indicate the priority or class of service (CoS) of the packet. The TC field can be mapped to the DSCP field in the IP header or the PCP field in the Ethernet header. The TC field can be used by MPLS routers to apply different per-hop behaviors (PHBs) such as queuing, scheduling, and dropping policies to different traffic classes12.
• DSCP: This is a 6-bit field in the IP header that can be used to mark packets according to the differentiated services (DiffServ) model. The DSCP field can indicate the per-hop behavior (PHB) that the packet should receive at each router along its path. The DSCP field can be mapped to the TC field in the MPLS label or the PCP field in the Ethernet header. The DSCP field can be used by IP routers to provide QoS for different traffic types34.
• PCP: This is a 3-bit field in the Ethernet header that can be used to mark packets according to the IEEE 802.1Q standard. The PCP field can indicate the priority or class of service (CoS) of the packet on an Ethernet LAN. The PCP field can be mapped to the TC field in the MPLS label or the DSCP field in the IP header. The PCP field can be used by Ethernet switches to provide QoS for different traffic types56.

References: MPLS Traffic Engineering - DiffServ-Aware Traffic Engineering, MPLS Traffic Engineering - DiffServ-Aware Traffic Engineering Configuration Guide, Differentiated services - Wikipedia, DSCP and Precedence Values - Cisco, 802.1Q VLAN IDs and Ethernet Interface Types - Juniper Networks, Introduction to Virtual LANs (VLANs) and Tagging - Ubiquiti Support and Help Center

P routers forward packets based on the LSP label. The LSP label is the label that corresponds to the label-switched path (LSP) that is established between two PE routers in an MPLS network. The LSP label is also called the outer label or the transport label, because it is used to transport packets across the MPLS core network. P routers are also called LSRs (label switch routers) or transit routers, because they switch packets based on their labels or remove the labels. P routers do not need to look at the IP header or any other information in the packet, except for the top label in the label stack. P routers perform one of three possible operations on labels: swap, pop, or PHP (penultimate hop popping). In a swap operation, the label is swapped with a new label, and the packet is forwarded along the path associated with the new label. In a pop operation, the label is removed from the packet, and the packet is forwarded based on its IP header or another label in the stack. In a PHP operation, the label is removed from the packet at the last P router before reaching the egress PE router, and the packet is forwarded without any label to the egress PE router.

The LSP label is different from other types of labels that may be used in MPLS networks, such as VPN labels or service labels. These labels are used to identify different VPNs or services that run over MPLS networks, such as Layer 2 VPNs, Layer 3 VPNs, traffic engineering, or QoS. These labels are also called inner labels or payload labels, because they are related to the payload of the packet. These labels are not used by P routers for forwarding decisions, but only by PE routers for delivering packets to their destinations.

Therefore, the answer is C.

References: Ericsson IP Networking - Routing Protocols, MPLS Fundamentals: Forwarding Labeled Packets - Cisco Press, MPLS Labels and Devices - NetworkLessons.com, Multiprotocol Label Switching - Wikipedia, VPN Packet Forwarding > MPLS/VPN Architecture Overview | Cisco Press, Basic concepts - Hewlett Packard Enterprise

Link-state routing protocols are one of the two main classes of routing protocols used in packet switching networks for computer communications, the other being distance-vector routing protocols. Examples of link-state routing protocols include Open Shortest Path First (OSPF) and Intermediate System to Intermediate System (IS-IS). The basic concept of link-state routing is that every node constructs a map of the connectivity to the network, in the form of a graph, showing which nodes are connected to which other nodes. Each node then independently calculates the next best logical path from it to every possible destination in the network. Each collection of best paths will then form each node’s routing table.

Two statements that are true about link-state routing protocols are:

• The advertisement exchange is mainly triggered by a change in the network. Link-state routing protocols use a flooding mechanism to distribute information about the network topology to all routers in the same area or domain. This information is encapsulated in link-state packets (LSPs) or link-state advertisements (LSAs), which contain information about the router, its directly connected links, and the state of those links. LSPs or LSAs are sent only when there is a change in the topology, such as a link failure or recovery, or when a periodic refresh timer expires. This way, link-state routing protocols can quickly adapt to network changes and maintain an accurate and consistent view of the network.
• Each router uses a reliable update mechanism to exchange topology information with its neighbors. Link-state routing protocols use a reliable update mechanism to ensure that all routers receive and acknowledge the LSPs or LSAs sent by their neighbors. This mechanism involves sending hello messages to establish and maintain adjacencies with neighbors, sending acknowledgment messages to confirm the receipt of LSPs or LSAs, and requesting missing or outdated LSPs or LSAs from neighbors. This mechanism ensures that all routers have a synchronized database of LSPs or LSAs, which is used to build a complete network connectivity map and to calculate the shortest path to destinations.

References: Link-state routing protocol - Wikipedia, Ericsson IP Networking - Routing Protocols