The sender announces the initial window size

The sender does not need to transmit the full window size of the message

TCPSliding window allows multiple packets to be sent before an acknowledgment is received

After the retransmission timer expires, the sender has not received the acknowledgment and will retransmit the unacknowledged data

The receiver needs to confirm the data packet of the sender

Sliding window size can only increase or stay the same

ISIS GThe R feature is enabled by default.

ISIS GR has a total of four timers.

ISIS GR notifies events and maintains neighbor relationships through CSNP messages.

ISIS GR defines a whole new TLV structure to support this feature.

[Huawei]interface GigabitEthernet 0/0/1 [Huawei-GigabitEthernet0/0/1]port link type trunk

[Huawei-GigabitEthernet0/0/1port trunk allow pass vlan 10

[Huaweijinterface GigabitEthernet 0/0/1

[Huawei-GigabitEthernet0/0/1]port link type access [Huawei GigabitEthernet0/0/1]ipsg enable

. [Huawei]interface GigabitEthernet 0/0/1

[Huawei-GigabitEthernet0/0l]port link-type access [Huawei-GigabitEthernet0/0/1 ]port-security enable

[Huawei]interface GigabitEthernet 0/0/1

[Huawei-GigabitEthernet0/0/1 ]port link type access [Huawei-GigabitEthernet0/0/1]port isolate enable

True

false

TRUE

FALSE

10

30

3.3

40

True

false

advertise vpnv4

to advertise irb

advertise 12vpn vpn

advertise irbv6

True

false

TRUE

FALSE

The AS number of the adjacent AS, listed in the AS in the BGP routing entry_ The far right of the Path list.

BGP Speaker When the route learned from the EBCP peer is advertised to the IBGP peer, the next hop attribute of the route information is not changed.

Local Prefs are only valid between EBGP peers and are not advertised to third-party ASs.

A route can only have one community attribute value.

R3's GE0/0/0 port and its neighbor are in different areas

Eth0/0/1 of the R3 router enables both IPv4 and IPv6 ISIS

R3 is Level-1 and L on the link where Eth0/0/0 is located evel-2 DIS

The circuit-level of Eth0/0/1 of the R3 router is Level-1-2

TRUE

FALSE

True .

false

BFDThe one-arm echo function must configure the local identifier and the terminal identifier

BPThe default destination IP address of the protocol packet of the D one-arm echo is 224.0.0.184

BAfter the FD one-arm echo function is enabled, the destination IP and source IP of BFD packets are the same

BFDThe one-arm echo function is suitable for scenarios where one device supports BD and the other device does not.

Support impo when BGP generates routes. There are two methods, rt and Network, and the Network method is more accurate.

By default, the default metric value of external routes imported by OSPF is 1, and the type of imported external routes is Type2.

ISIS level-2 netAfter the work route is imported to level-1, if the import policy is not manually configured, a routing loop will be formed.

Importing IBGP routes into OSPF may cause routing loops.

A carried by routeSPATH attribute to filter routes received from BGP neighbors. For example the command peer xxxx as-path-fliter import

Route apply clause in policy

A carried by routeSPATH attribute to filter routes sent to BGP neighbors. For example the command peer xxxx as-path-ilter export

if-match clause in Route-policy

By default, matching is performed according to the "depth first" principle.

By default, match pe first rmit, then match the order of deny.

By default, according to Rule-ID, matching from small to large.

There is only one matching order and cannot be modified.

Advanced ACL can be applied to route In policy, filter routes

entry pemit :: 0 less-equal 128 means allow all IPv6 routes to pass through

ifMore than one node is defined in Route-policy, and at least one of each node should have a matching mode of permit

Route-Policy can filter only default routes

IGMPv2Specific group queries are not supported

IGMPv2Message types include member leave messages

IGMPv1Support general group query

IGMPv1The message type does not contain a member leave message

VPConfigure 1000:1000 under N both evpn.

EVPConfigure 1000:1000 under N both

Configure 1000:100 under EVPN0 export

VPConfiguration under N 10:10 both.

100, 200, 300

400, 300, 200, 100

100, 200, 300, 400

300, 200, 100

Inter-Area Plink of refixLSA State ID, contains prefix information

Router-LSA and Network-LSA do not contain routing information

when Intra-Area PReferenced of refixLSA Link State Type 2 o'clock,Referenced Link State ID containsInterface ID of the DR

Inter-Area PrefixLSA also contains Link-local information

BGP packets can be used to exchange VPN routing information between CEs and PEs

Hub-CE and When the Hub-PE transmits routing information, the Hub-PE It is necessary to configure a route that allows the receiving AS number to be repeated once to receiveRoutes advertised by the Hub-CE

Hub-CE and Hub-PE, Spoke-PE with Spoke-CEs can use OSPF to exchange routing information

Spoke- Establish an MP-IBGP peer relationship between PEs to exchange VPN routing information.

configure staticARP binding table

Configure IPSG

Limit what the interface allows to learnDHCP The maximum number of Snooping binding entries

configureDAI

This router is the DR

This router has established an adjacency relationshipC. This router supports external route import

The router of this router ID for 10.0.12.1

Type1

Type2

Type3

Type4

Type5

TRUE

FALSE

isis cost

isis timer hello

isis circuit-type

isis circuit-leve1

Configuring CE Dual-homing Networking at the Access Layer

VPN FRR

VPN-GR

PE- Private network IP routing FRR between CEs

Layer 2 gateway:It is used to solve the problem of tenants accessing the VXLAN virtual network, and can also be used for subnet communication of the same VXLAN virtual network.

Layer 3 gateway:Used for cross-subnet communication of VXLAN virtual networks and access to external networks.

VXLAN Layer 3 gateways can be divided into centralized gateways and distributed gateways.

The Layer 2 gateway is bound to the VPN instance.

True

false

Agile Controller-Campus

Agile Controller-WAN

Agile Controller-DCN

Type5 routes carry Layer 3 VNI.

Type5 routes carry both Layer 2 VWI and Layer 3 VNI.

IP PThe refx field can carry both the host IP address and the network segment address.

Type5 is IP prefix routing.

True

false

802.3z

802.3ab

802.3ad

802.3af

Preemption mode

The priority of the virtual router

Preemption delay

virtual IP address

Type5

Type4

Type1

Type2

Type3

Private network label by MP-BGP carries and distributes routes when delivering routes, and public network labels are distributed by LDP.

MPLS BGP VPNTwo layers of labels are used in the network: public network labels (also called outer labels) and private network labels (also called inner labels).

By default, the router assigns the same label value to all VPNv4 routes destined for the peer end.

exitThe PE uses the inner label when judging which egress CE the packet should be sent to.

The 2022::/64 route will appear in the IP routing table

The 2019::/64 route will appear in the IP routing table

The 2020::/64 route will appear in the IP routing table

The 2021::/64 route will appear in the IP routing table

data link layer header

upper layer data

network layer header

path record

network layer tail

TRUE

FALSE

TRUE

FALSE

The transmission node device will replace the existing stack top label (outermost label) with the label allocated by the next hop device.

When IP Packet enters MPLS domain, check the destination IP Tunne corresponding to the addressl ID Is the value 0x0 if Tunnel ID value is 0x0, then enter MPLS forwarding process.

when IP Packet enters MPLS domain, MPLS The boundary device is in the packet layer 2 header and IP Insert a new label between the headers

sign.

By default, PHP is supported Egress The label value assigned by the node to the penultimate hop node is 3.

existIn the hello packet sent by the OSPF neighbor in the NSSA area, in the option field ofN position 0, E position 1

NSSAA default LSA will be automatically generated in the area to access the external network

The NSSA area will generate seven types of L SAs to advertise external routes. The FA addresses in the seven types of L SAs are used to prevent loops.

existIn the hello packet sent by the OSPF neighbor in the NSSA area, the position of the option field is 1, and the position of E is 0.

Trap, Get and Set

Get, Set and Getnext

Get, Set, Getnext and GetBulk

Get, Set and GetBulk

Trap only

BGP4+ carries the next hop address of IPv6 routes through the Next_hop attribute

There is no Next_hop attribute in BGP4+

BGP4+ carries the next hop address of the route through the Network Address of Next Hop in the MP_Reach_NLRI attribute

BGP4+ carries the prefix and mask length of IPv6 routes through the NLRI attribute

Open

Keepalive

Update

Hello

IGMP Snooping does not consume the CPU of the switch

IGMP Snooping solves the problem of multicast multicast broadcast at Layer 3

IGMP Snooping runs at the link layer and is a multicast constraint mechanism on a Layer 2 Ethernet switch to manage and control multicast groups.

IGMP Snooping establishes a MAC multicast address table by monitoring the IGMP messages sent by the host.

Router HW1 strips the label and looks forFIB uses IP destination address

Router HW1 will use LDP to create an LSP and create a new path in LFIB for the label carried in the packet

Router HW1will discard the message

Router HW1The message will be forwarded with the default label

By default, the router assigns the same label value to all VPNv4 routes destined for the peer PE.

The egress PE uses the inner layer label when judging which egress CE the message should be sent to.

MPLS BGP VPN uses two layers of labels, the public network label (also called the outer label) and the private network label (also called the inner label).

The private network label is used by NP-BGP It is carried and distributed when the route is passed, and the public network label is set by LDP Agreement distribution.

0

15

20

10

BGP

static routing protocol

OSPF

MPLS LDP

Hello packets are sent to the multicast address 224.0.0.5

pass throughHe11o message elects DR in multi-router network segment

Used periodically between routersHello, keep in touch

at P1M- In the SM network, the newly started multicast router needs to useHello message to discover neighbors and maintain neighborsresidential relationship

Route CB, Route A

Route B and Route

will be selected at the same time-and form load sharing

Route B

30

80

50

40

True

false

TRUE

FALSE

In the NSSA area, filtering for external route import and advertisement can be configured on ASBR or ABR.

Filtering for three types of LSAs needs to be configured on ABRs between OSPF areas

Filter LSA based on interface, can filter in and out direction, except Grace All LS except LSAA

When calculating routes based on the link state database, use filter-policy import command, this filtering method only affects the routing entries in the routing table. plus, for OSPF the link state database has no effect

The next-hop router of router HW has no path to reach the destination address

Ping was successful, but congestion occurred on the path to the destination

ICMP packets can reach the destination address, but the destination device fails to reply

router HWThere is no valid route to the destination address

There is a firewall in the remote destination network, and I have not been releasedCMP traffic

Use traffic shaping in the ingress direction and traffic policing in the egress direction

For traffic shaping, routers buffer excess packets until bandwidth is available again

Traffic policing uses the token bucket algorithm, and traffic shaping uses the SPD algorithm

For traffic policing, it can be more thanCIR Traffic Adjustment Buffer Usage

For traffic shaping, can be more thanCIR Traffic Adjustment Buffer Usage

The routing entry in the peer BGP routing table is not optimal.

The next hop address of the BGP routing entry is unreachable

Peer ignore is configured on the peer

The peer is configured with active-route-advertise

30

50

80

40

The outer label of MPLS VPN is called the private network label, and the inner label is called the public network label.

By default, the outer label is popped before the data packet is forwarded to the last hop device.

The outer label is used for Correctly send packets to the corresponding VPN on the PE device

The outer label of MPLS VPN is assigned by the LDP protocol or statically, and the inner label is assigned by the MP-BGP neighbor of the opposite end

ASBR cannot be stored in stub area.

Virtual connections cannot pass through stubsarea.

Type injection is not allowed in stub area7 LSA

The backbone area cannot be configured as a stubarea.

PIM Join information.Every 60 Sent once per second to refresh the upstream router m for the multicast treeroute State

PIM Join message per 3 Sent once every minute to refresh the upstream router mroute for the multicast tree State

the upstream router sends a PIMJoin acknowledgement in response to each received from the downstream router

PIM Join message PIM Join message. Only sent when the multicast tree is first established