Consider Again the Sdn Openflow Network

Network Layer

Kurose & Ross, Affiliate four, Problem P4.

Consider the switch shown beneath. Suppose that all datagrams take the aforementioned fixed length, that the switch operates in a slotted, synchronous manner, and that in i time slot a datagram can exist transferred from an input port to an output port. The switch fabric is a crossbar then that at most one datagram can be transferred to a given output port in a fourth dimension slot, only different output ports tin receive datagrams from different input ports in a unmarried time slot. What is the minimal number of time slots needd to transfer the packets shown from input ports to their output pots, assuming any input queue scheduling lodge you want (i.e., it need not take HOL blocking)? What is the largest number of slots needed, assuming the worst-example scheduling society you can devise, assuming that a non-empty input queue is never idle?
Kurose & Ross, Chapter four, Problem P5.

Consider a datagram network using 32-bit host addresses. Suppose a router has four links, numbered 0 through three, and packets are to exist forwarded to the link interfaces as follows:

a. Provide a forwarding tabular array that has five entries, uses longest prefix matching, and forward packets to the right link interfaces.

b. Describe how your forwarding table determines the advisable link interface for datagrams with destination addresses:

11001000 10010001 01010001 01010101
11100001 01000000 11000011 00111100
11100001 10000000 00010001 01110111
Kurose & Ross, Chapter 4, Trouble P8.

Consider a router that interconnects three subnets: Subnet 1, Subnet 2, and Subnet 3. Suppose all of the interfaces in each of these iii subnets are required to take the prefix 223.1.17/24. Also suppose that Subnet 1 is required to support at least 62 interfaces, Subnet 2 is to support at least 95 interfaces, and Subnet 3 is to support at least sixteen interfaces. Provide three network addresses (of the class a.b.c.d/10) that satisfy these constraints.
Kurose & Ross, Chapter 4, Trouble P14.

Consider sending a 2400-byte datagram into a link that has an MTU of 700 bytes. Suppose the original datagram is stamped with the identification number 422. How many fragments are generated? What are the values in the various fields in the IP datagram(s) generated related to fragmentation?
Kurose & Ross, Chapter 4, Problem P19.

Consider the SDN OpenFlow network show below.

Suppose that the desired forwarding behavior for datagrams arriving at s2 is as follows:
- any datagrams arriving on input port 1 from hosts h5 or h6 that are destinated to hosts h1 or h2 should exist forwarded over output port 2;
- any datagrams arriving on input port two from hosts h1 or h2 that are destined to hosts h5 or h6 should exist forwarded over output port 1;
- any arriving datagrams on input ports 1 or two and destned to hosts h3 or h4 should exist deliverd to the host specified;
- hosts h3 and h4 shoul dbe able to transport datagrams to each other.
Specify the period table entries in s2 that implement this forwarding behavior.
Kurose & Ross, Chapter 4, Problem P22.

Consider again the SDN OpenFlow network shown above. Suppose nosotros desire switch s2 to office as a firewall. Specify the flow table in s2 that implements the following firewall behaviors (specify a different flow table for each of the four firewalling behaviors below) for delivery of datagrams destined to h3 and h4. You practice not need to specify the forwarding behavior in s2 that forrad traffic to other routers.

a. Only traffic arriving from hosts h1 and h6 should exist delivered to hosts h3 or h4 (i.e., that arriving traffic from hosts h2 and h5 is blocked).

b. Only TCP traffic is allowed to be delivered to hosts h3 or h4 (i.due east., that UDP traffic is blocked).

c. But traffic destined to h3 is to be delivered (i.e. all traffic to h4 is blocked).

d. Simply UDP traffic from h1 and destined to h3 is to be delivered. All other traffic is blocked.
Kurose & Ross, Chapter 5, Problem P8.

Consider the three-node topology shown below. Rather than having the link costs shown in the figure, the link costs are c(x,y) = 3, c(y,z) = 6, c(z,x) = 4. Compute the distance tables afterwards the initialization step and after each iteration of a synchronous version of the altitude-vector algorithm.
Kurose & Ross, Affiliate 5, Problem P14.

Consider the network shown below. SUppose AS3 and AS2 are running OSPF for their intra-As routing protocol. Suppose AS1 and AS4 are running RIP for their intra-Equally routing protocol. Suppose eBGP and iBGP are used for the inter-AS routing protocol. Initially suppose there is no physical link between AS2 and AS4.

a. Router 3c learns about prefix x from which routing protocol: OSPF, RIP, eBGP, or iBGP?

b. Router 3a learns almost ten from which routing protocol?

c. Router 1c learns about x from which routing protocol?

d. Router 1d learns about x from which routing protocol?
Kurose & Ross, Chapter 5, Problem P15.

Referring to the previous problem, once router 1d learns almost $x$. It will put an entry $(x,I)$ in its forwarding table.

a. Will $I$ be equal to $I_1$ or $I_2$ for this entry? Explain why in one judgement.

b. At present suppose that there is a concrete link betwixt AS2 and AS4, shown by the dotted line. Suppose router $1d$ learns that $10$ is accessible via AS2 as well as via AS3. Will $I$ be set to $I_1$ or $I_2$? Explicate why in one sentence.

c. Now suppose there is another AS, called AS5, which lies on the path between AS2 and AS4 (not shown in diagram). Suppose router 1d learns that 10 is attainable via AS2 AS5 AS4 as well equally via AS3 AS4. Will $I$ be set to $I_1$ or $I_2$ ? Explain why in i sentence.
Kurose & Ross, Affiliate 5, Problem P16.

Consider the post-obit network.

ISP B provides national courage service to regional Internet access provider A. ISP C provides national courage service to regional ISP D. Each Internet service provider consists of one Every bit. B and C peer with each other in two places using BGP. Consider traffic going from A to D. B would adopt to manus that traffic over to C on the West Coast (and then that C would take to absorb the price of carrying the traffic cross-state), while C would prefer to get the traffic via its East Coast peering indicate with B (so that B would accept carried the traffic beyond the country). What BGP mechanism might C use, so that B would mitt over A-to-D traffic at its East Declension peering bespeak? To answer this question, yous will non demand to dig into the BGP specification.