UIDL abbreviates precise-ID listing. When a POP3 purchaser problems the UIDL command, the server responds with the
Question:
UIDL abbreviates "precise-ID listing". When a POP3 purchaser problems the UIDL command, the server responds with the specific message ID for all of the messages present in the users mailbox. This command is useful for "down load and hold". By maintaining a file that lists the messages retrieved in in advance sessions, the consumer can use the UIDL command to determine which messages at the server have already been visible.
Problem thirteen.
A) For a given enter of area name (including ccn.Com), IP deal with or community administrator call, whois database can be used to discover the corresponding registrar, whois server, dns server, etc.
F) An attacker can use the whois database and nslookup tool to decide the IP address tiers, DNS server addresses, and so on. For the target organization.
G) If below an attack a sufferer can analyze the supply address of packets, the sufferer can then use whois to attain records about domain from which attack is coming and likely inform the administrators of the foundation area.
Problem 14. No. Because the hyperlink is complete duplex, you've got 128 kbps in each direction, and the importing does now not interfere with the downloading.
Problem 15. There are N nodes in the overlay network. There are N(N-1)/2 edges.
Problem 16. A) In this situation, every of the five Gnutella customers immediately learns that it has one much less neighbor. Consider such a 5 customers, called, Bob. Suppose Bob has simplest 3 friends after X drops out. Then Bob desires to establish a TCP reference to every other peer. Bob must have a sparkling list of active friends; he sequentially contacts friends on this listing until one accepts his TCP connection attempt.