Grab latest Ericsson ECP-206 Dumps as PDF Updated on 2024 [Q17-Q32]

Explanation
A reason for using VLANs in an IP network is to isolate hosts within the same IP subnet. VLANs (Virtual LANs) are logical grouping of devices in the same broadcast domain. VLANs are usually configured on switches by placing some interfaces into one broadcast domain and some interfaces into another. Each VLAN acts as a subgroup of the switch ports in an Ethernet LAN. VLANs allow network administrators to group hosts together even if the hosts are not directly connected to the same network switch. By using VLANs, hosts within the same IP subnet can be separated into different broadcast domains, which enhances security, reduces network congestion, and simplifies network management78.
References: 8 Different Types of VLANs in TCP/IP Networks, What is a VLAN? – Study-CCNA

Explanation
The action that will influence BGP route selection within your AS is changing the default value of the local preference attribute. The local preference attribute is used to indicate the preference of a path among multiple paths learned from different external BGP neighbors or autonomous systems (ASes). The higher the local preference value, the more preferred the path is within your AS, and vice versa. The default value of local preference is 100, but you can change it using route maps or other configuration methods on your BGP routers. References: Ericsson IP Networking – Routing Protocols, BGP Attributes and Path Selection, BGP Local Preference Attribute: Controlling Traffic Like a Pro

Explanation
Two statements that are true regarding the LSP are:
The LSP refers to a sequence of routers that forward the MPLS packet based on labels. An LSP is a Label Switched Path, which is a path through an MPLS network that is established by signaling protocols such as LDP or RSVP-TE. An LSP consists of a sequence of routers (called Label Switching Routers or LSRs) that forward packets based on labels rather than IP addresses. Labels are short fixed-length identifiers that are attached to packets at the ingress router and removed at the egress router. Labels can be swapped or popped at intermediate routers according to their label forwarding tables78.
The LSP refers to a sequence of routers that add, remove, or change label values along the path. As mentioned above, an LSP consists of a sequence of routers that forward packets based on labels. Along the path, different routers may perform different operations on the labels depending on their role and configuration. The ingress router adds one or more labels to the packet before sending it into the MPLS network. The egress router removes all labels from the packet before sending it out of the MPLS network. The intermediate routers may swap one label with another label according to their label forwarding tables. This process is called label switching78.
References: MPLS Fundamentals: 3 – MPLS Packet Forwarding, Multiprotocol Label Switching – Wikipedia

Explanation
The correct ordering (outer to inner) of packet headers in an IP/MPLS packet is Ethernet, MPLS, IP. An IP/MPLS packet is a packet that is encapsulated with an MPLS label stack between the Ethernet header and the IP header. The Ethernet header contains the source and destination MAC addresses and the EtherType field that indicates the type of the payload. The MPLS label stack contains one or more labels that are used for forwarding decisions by the MPLS routers. Each label consists of four fields: label value, experimental bits, bottom of stack, and time to live. The IP header contains the source and destination IP addresses and other information for routing and fragmentation. The order of the headers is important because it determines how the packet is processed by different devices in the network12.
References: MPLS Label Stack – Cisco, MPLS Fundamentals: 3 – MPLS Packet Forwarding

Explanation
iBGP works by exchanging routing information between two or more routers within an AS. Each router sends its own routing table to its neighbors, which contains information about the networks it knows and how they can be reached from that router. By default, iBGP neighbors only share BGP routes learned from eBGP neighbors, which are routers in different ASes. This is because iBGP assumes that all routers within an AS have consistent internal routing information provided by an IGP, such as OSPF or IS-IS. Therefore, iBGP neighbors do not need to share IP address information of loopbackinterfaces or directly connected interfaces, unless explicitly configured to do so by using commands such as neighbor update-source or network.
References: iBGP Ultimate Guide | How iBGP Is Different From eBGP, Ericsson IP Networking – Routing Protocols

Explanation
The correct order of DiffServ priority (highest to lowest) for the DiffServ classes: Default Forwarding (DF), Network Control (NC), Assured Forwarding (AF), and Expedited Forwarding (EF) is EF, NC, AF, DF.
DiffServ is a QoS model that classifies and prioritizes traffic into different service classes based on the DSCP field in the IP header. The DSCP field is a 6-bit field that can encode up to 64 different per-hop behaviors (PHBs). The DiffServ classes are predefined groups of PHBs that have similar characteristics and requirements. The four main DiffServ classes are:
EF: This class provides the highest priority and lowest delay for real-time applications such as voice and video. The DSCP value for EF is 101110 or 46 in decimal12.
NC: This class provides the second highest priority and low delay for network control traffic such as routing protocols and network management. The DSCP value for NC is 110000 or 48 in decimal12.
AF: This class provides four levels of assured forwarding with different drop probabilities for each level. AF is suitable for applications that require guaranteed bandwidth and delivery assurance, such as web browsing and email. The DSCP values for AF range from 001010 to 011110 or 10 to 46 in decimal12.
DF: This class provides the lowest priority and best-effort service for applications that can tolerate packet loss and delay, such as file transfer and backup. The DSCP value for DF is 000000 or 0 in decimal12.
References: Differentiated Services – Wikipedia, DSCP – Differentiated Services Code Point – Mpirical

Explanation
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

Explanation
A P router is a provider router that is part of the service provider’s core network in an MPLS environment. A P router does not have any customer routes or VPN information, but only has information about how to reach other P routers and PE routers in the same MPLS domain. A P router performs label switching, which means that it forwards labeled packets based on their top label in the label stack. A P router can perform two possible label actions:
Swap: The P router replaces the incoming label with a new label that corresponds to the next hop along the label-switched path (LSP). The new label is determined by looking up the label forwarding information base (LFIB) based on the incoming label and interface.
PHP: The P router removes the top label from the packet at the penultimate hop before reaching the egress PE router. This is done to avoid an extra lookup on the egress PE router, which can forward the packet based on its IP header or another label in the stack.
A P router does not perform push or drop actions on labels. A push action means adding one or more labels to the packet, which is done by an ingress PE router when initiating an LSP. A drop action means discarding a packet, which is done by any router when there is no matching entry in its LFIB or routing table. References: Provider (P) Router in IP MPLS Network – Cisco Community, MPLS Fundamentals: Forwarding Labeled Packets – Cisco Press, MPLS Label Switching | MPLS Operation | Push, Swap,Push IPCisco

Explanation
A BGP session is established between two routers by sending a unicast OPEN message. BGP uses TCP as its transport protocol, which means that before exchanging any BGP information, a TCP connection must be established between the routers. The TCP connection uses port 179 as both source and destination port. After establishing a TCP connection, each router sends an OPEN message to its neighbor, containing parameters such as BGP version number, AS number, hold time, BGP identifier, and optional capabilities. The OPEN message also serves as a keepalive message for BGP. If both routers agree on these parameters, they proceed to exchange UPDATE messages containing routing information and establish a BGP session.
A BGP router does not send a NOTIFICATION message to establish a session, but rather to terminate a session due to an error or a manual shutdown. A BGP router does not send a CONNECT message, as this is a TCP state, not a BGP message. A BGP router does not send a multicast HELLO packet, as this is an OSPF message, not a BGP message. References: BGP Neighbor States > BGP Fundamentals | Cisco Press, Demystifying BGP Session Establishments – Packet Pushers, The TCP/IP Guide – BGP Connection Establishment: Open Messages

Explanation
Regarding the BGP decision algorithm, two statements that are correct are:
A higher local-preference attribute will be favored over a lower local-preference attribute. The local-preference attribute is used by BGP routers within an AS to indicate their preference for an exit point from the AS. A higher value means a more preferred path. The local-preference attribute is exchanged only between iBGP peers and does not leave the AS boundary89.
A path cannot be considered if the next-hop is inaccessible. The next-hop attribute is used by BGP routers to determine where to forward packets for a given destination prefix. The next-hop attribute is usually set to the IP address of the eBGP neighbor that advertises the prefix. If there is no IGP route to reach the next-hop address, the path is marked as invalid and ignored by BGP1011.
The other two statements are incorrect because:
The most important criteria is not the administrative distance, but rather the weight attribute. The administrative distance is used by routers to choose between routes from different routing protocols, not within BGP. The weight attribute is a Cisco-specific attribute that is used by BGP routers to prefer one path over another within the same router. The weight attribute is local to the router and not advertised to any peers1213.
A lower local-preference attribute will not be favored over a higher local-preference attribute, as explained above.
References: BGP Best Path Selection Algorithm – Cisco, Understanding BGP Local Preference Attribute – NetworkLessons.com, BGP Next Hop Attribute Explained – NetworkLessons.com, BGP Next Hop Processing
– Cisco Press, BGP Weight Attribute Explained – NetworkLessons.com, Understanding BGP Weight Attribute
– Cisco Community

Explanation
The subnet address for 10.57.126.156/29 is 10.57.126.152. To find the subnet address, we need to perform a bitwise AND operation between the IP address and the subnet mask. The subnet mask for /29 is
255.255.255.248, which in binary is 11111111.11111111.11111111.11111000. The IP address in binary is
00001010.00111001.01111110.10011100. The result of the AND operation is
00001010.00111001.01111110.10011000, which in decimal is10.57.126.152. References: Ericsson IP Networking – IP Addressing, Software Installation and Upgrade Overview (Junos OS)

Explanation
The route type that is restricted in an OSPF stub area is type 5. Type 5 LSAs are external LSAs that are generated by ASBRs to advertise routes from other routing domains or protocols into OSPF. Type 5 LSAs are flooded throughout the OSPF domain by default, except in stub areas. Stub areas are special OSPF areas that block type 5 LSAs from entering the area in order to reduce the size of the LSDB and the routing table. Stub areas only receive information about intra-area routes (type 1 and 2 LSAs), inter-area routes (type 3 LSAs), and a default route (type 3 LSA with destination 0.0.0.0/0) from the ABRs910.
References: Introduction to OSPF Stub Areas – NetworkLessons.com, What Are OSPF Areas and Virtual Links? – Cisco

Explanation
The statement that accurately defines an Autonomous System (AS) is that an AS is a set of routers under a single administration, using an interior gateway protocol and common metrics to route packets within the AS.
An AS is a logical grouping of networks that share a common routing policy and operate under a single administrative authority. An AS can be a single network or a collection of networks that are interconnected by routers. An AS uses an interior gateway protocol (IGP), such as OSPF or IS-IS, to exchange routing information within the AS. An IGP uses common metrics, such as hop count or bandwidth, to determine the best path to each destination within the AS. An AS also has a unique number assigned by IANA, called an AS number (ASN), which identifies the AS in interdomain routing .
References: [Autonomous system (Internet) – Wikipedia], [What Is an Autonomous System? – Cisco]

Explanation
A label-edged router (LER) is a PE router. A PE router is a provider edge router, which is a router that connects an MPLS network to a customer network. A LER is a term used in MPLS to describe a router that resides at the ingress and egress points of an MPLS network, handling both labelled and unlabelled packets. A LER performs label operations such as adding, removing, or swapping labels on packets entering or leaving the MPLS network34.
References: What is Label Edge Router (LER)? – Definition from Techopedia, LER – Label Edge Router – Mpirical

Explanation
Referring to the exhibit, the service provider should implement L3VPN using the MP-BGP protocol to connect the sites for two customers (indicated in red and green in theexhibit). L3VPN is a type of VPN that uses MPLS to provide IP connectivity between customer sites across a service provider network. L3VPN allows customers to use overlapping or identical IP addresses without causing conflicts or requiring NAT. L3VPN uses MP-BGP to exchange VPN routes between PE routers, which are routers that connect customer networks to the service provider network. MP-BGP is an extension of BGP that can carry multiple address families, such as VPNv4 or VPNv6, along with additional attributes, such as route distinguisher (RD) and route target (RT). RD is used to make customer routes unique within the service provider network, while RT is used to control which routes are imported or exported between different VPNs3 .
References: L3VPN – Layer 3 Virtual Private Networks – Mpirical, [Use of MP-BGP Extensions for IPv6 Interdomain Routing]

Explanation
The CLI command to obtain the software version in Ericsson Router 6000 products is show version. This command displays information about the software release, the hardware model, the serial number, the uptime, and the boot image of the router. References: [ERICSSON SMARTEDGE 600 HARDWARE MANUAL Pdf Download | ManualsLib], Ericsson Router 6000 Series – Ericsson