04 - Routers and Gateways

 1. ______: a device that interconnects with two or more computer networks, which then interchange packets with each other




  DNS Server

 2. Like a Bridge a Switch ……………………….. Data packets received from one connection are only forwarded if they have a valid destination MAC address on the other connection. Unlike Bridges, Switches can have many connections.

  has a list of ISPs to which it can send data

  has a table of MAC addresses for each connected machine

  has a list of DNS servers for each connected machine

  None of the above

 3. Homes and businesses use a router to connect to the internet. A router can often incorporate a _______ within the hardware.

  DNS server

  Broadband connection


  Server for ISPs

 4. A gateway is a piece of____________ used in telecommunications for communications networks that allows data to flow from one discrete network to another

  networking hardware

  networking card chip

  hardware, that is identical to a router

  networking software

 5. Gateways are distinct from routers or switches in that they communicate using more than one protocol and can operate at any of the 7 layers of the OSI model.



 6. The term gateway can also loosely refer to a computer or computer program configured to perform the tasks of a gateway, such as a default gateway.



 7. A router is a networking device that forwards data packets between computer networks. Routers perform the ……………………

  creation of the packet header

  traffic directing functions on the Internet

  blocking of all security protocols

  None of the above

 8. When a data packet comes in on one of the lines, the router ……………………………………... Then, using information in its routing table or routing policy, it directs the packet to the next network on its journey.

  reads the network address information in the packet to determine the ultimate destination.

  checks to see that the ISP is on the DNS server list

  reads the network packet information and returns it to sender

  None of the above

 9. The most familiar type of routers are home and small office routers that simply ………………

  send binary sequences through a Modem to a single DNS server

  forward IP packets between the home computers and the Internet

  carry out the function of a DNS server (checking IP addresses against a database)

  None of the above

 10. Though routers are typically dedicated hardware devices, software-based routers also exist.



 11. When multiple routers are used in interconnected networks, the routers can exchange information about destination addresses using a routing protocol. Each router builds up a ………………….

   routing table listing the preferred routes between any two systems on the interconnected networks.

  reputation and customers purchase routers with the highest rank

  None of the above

  anti virus software list that is used to block insecure connections

 12. A router may have interfaces for different types of physical layer connections, such as …………….

  ISPs, DNS servers and Modems

  None of the above

   copper cables, fiber optic, or wireless transmission

  Hubs, switches and re-routers

 13. Routers may also be used to connect two or more logical groups of computer devices known as ………..., each with a different network prefix.



  ISP servers


 14. The largest routers (such as the Cisco CRS-1 or Juniper PTX) interconnect the various ISPs, or may be used in large enterprise networks



 15. Routers are also often distinguished on the basis of the network in which they operate. A router in a local area network (LAN) of a single organisation is called an…………..

  exterior router

  inferior router

   interior router

  superior router

 16. An ………..directs packets between hosts in one LAN and hosts in another LAN. A router that is operated in the Internet backbone is described as ……………………..

  exterior router

   interior router

  superior router

  inferior router

 17. The main purpose of a router is to ………………………………... destined either for its own networks or other networks.

  search for the right information and capture it

  connect multiple networks and forward packets

  send multiple messasges(via email or telnet) at once

  connect multiple DNS servers to each other so that web addresses have an identity

 18. When a router receives a packet, it searches its routing table to find the best match between the destination IP address of the packet and one of the addresses in the routing table



 19. Another function a router performs is to decide ……………………………..when multiple queues exist

  which anti virus software the network should employ

  which URL to delete or add to the data bank

  which ISPs shoud be blocked permanently

  which packet should be processed first

 20. Yet another function a router performs is called policy-based routing where special rules are constructed to override the rules derived from the routing table when a packet forwarding decision is made



 21. Read the following excerpt on the history of routers and decide whether it is true or false
The concept of an "Interface computer" was first used by Donald Davies for the NPL network in 1966.[19] The Interface Message Processor (IMP), conceived in 1967 for use in the ARPANET, had fundamentally the same functionality as a router does today



 22. A gateway is often associated with both; a router, which knows where to direct a given packet of data that arrives at the gateway, and a ……………………

  None of the above

  switch, which furnishes the actual path in and out of the gateway for a given packet.

  ISP - which hosts the internet for different clients

  DNS server - which looks up IP addresses

 23. A gateway is an essential feature of most routers, although other devices (such as any PC or server) can function as a gateway.
If the networks share the same protocols, for example TCP/IP, routers are used. When protocols differ between networks, a gateway is used instead.



 24. Gateways regulate traffic between ……………….., while routers regulate traffic between similar networks

  two different types of cables

  two seperated networks

  two LAN only networks

  two dissimilar networks

 25. Both Routers and Gateways are used to regulate network traffic between two or more separate networks



 26. Gateways are the ________and _______ of a network and are sometimes thought of as a protocol translator/converter.

  packet / switch

  entrance / exit

  end / exit

  gate / ungate

 27. The main use of a gateway is to connect different networks of different architectures and this is called………….

  cache working

  missed calls

  gate logic


 28. The gateway must always be a physical object



 29. The gateway can be built into the network's subsystems and into the network software instead of being bound to a single location.



 30. The gateway takes in a ________from an external node and strips it down, removing all information except the raw data.




  master site