The Bits and Bytes of Computer Networking. Week 4: Network Services Already Passed

The Bits and Bytes of Computer Networking. Week 4: Network Services Already Passed What transport layer protocol does DNS normally use? UDP; While DNS over TCP does exist, UDP is the most common protocol. A DNS TTL determines what? How long a DNS entry is allowed to be cached; TTL stands for Time to Live and determines how long a DNS entry can be cached How many root servers are there? 13; There are 13 root servers. An A Record contains what? IPv4 address; An A record contains an IPv4 address Select all that are true. One domain name can point to one IP; This is a valid DNS setup One domain name can point to many IPs; this is a valid DNS setup. Many domain names can point to the same IP; This is a valid DNS setup. MX stands for ________. Mail exchange; An MX record stores a mail server's IP. A fully qualified domain name can contain how many characters? 255; An FQDN is limited to a total length of 255 characters. What are the four things that all computers need configured in order to operate on a modern network? Check all that apply. An IP address; All computers need these four things configured in order to operate on a modern computer network. a name server; Computers need a name server in order to operate on a network. a subnet mask; All computers need these four things configured in order to operate on a modern computer network. a default gateway; All computers need these four things configured in order to operate on a modern computer network. When using Fixed Allocation DHCP, what's used to determine a computer's IP? a MAC address; Fixed Allocation DHCP ensures that computers receive an IP address reserved for it via its MAC address. The process by which a client configured to use DHCP attempts to get network configuration information is known as _________________. DHCP Discovery; DHCP Discovery is how a client determines configuration information. NAT addresses concerns over the dwindling IPv4 address space by ___________________. allowing computers using non-routable address space to communicate with the Internet; NAT allows networks to use non-routable address space for their internal devices. What technique allows for inbound traffic through a NAT? Port forwarding ; Port forwarding is a technique that allows for inbound traffic through a router configured to NAT. The total number of IPv4 addresses is approximately: 4.2 billion; There are approximately 4.2 billion IPv4 addresses. Two-factor authentication is_________________________. a method where you need more than a username and a password; Two-factor authentication requires a username/password and something extra VPNs are known as a _____ protocol. tunneling; VPNs are tunneling protocols. A proxy is something that _______________________. communicates on behalf of something else; While proxies are many things, they primarily communicate on behalf of something else. A technique that's used to route traffic to different destinations, depending on factors like location, congestion, or link health, is known as _____. anycast; Anycast lets you route traffic depending on many factors. A concept that involves iterating over a list of items one by one in an orderly fashion is known as _______. Round robin; Round robin ensures a fairly equal distribution across its members. Administration and definition of TLDs are handled by a non-profit organization known as _______. ICANN is responsible for maintaining the global domain name system. When a range of IP addresses is set aside for client devices, and one of these IPs is issued to these devices when they request one, this is known as _______ allocation. dynamic; Dynamic Allocation DHCP will assign a random IP from a pool of IPs to a device that needs one. VPN stands for _______ Virtual Private Network; A VPN allows a device to establish an encrypted tunnel to another network. A company moves a popular website to a new web host. Which of the following will change as a result? Internet Protocol address; The IP address will certainly change. However, with DNS in place the name stays the same and users will never know that the website moved. The "www" portion of a domain is known by which of the given options? Check all that apply. Top Level Domain (TLD) name subdomain Host name Fully Qualified Domain Name (FQDN) subdomain; A subdomain like "www" precedes the domain name and is used to further identify a system and its purpose. You didn't select all the correct answers Which of the following allows computers on a network to automatically receive address assignment information? Dynamic Host Protocol; DHCP is used to automatically assign IP addresses to devices on a network. Network Address Translation (NAT) technology provides a major benefit for which of these network problems? Port Preservation, Address exhaustion, Assigning Internet Protocol address blocks, Routable addresses Routable address; Incorrect Not quite. Please review the videos in the "Network Address Translation" module for a refresher. Which technology uses a tunneling protocol? Virtual Private Network; A VPN uses a tunnel to maintain private and secure communications. What port on a name server is used for User Datagram Protocol (UDP) name request packets? 53; DNS uses port 53 over UDP for name resolution communications. A complete Fully Qualified Domain Name (FQDN) is limited to how many characters? 255; A complete FQDN can be up to 255 characters. Which of the following is NOT configured by a Dynamic Host Protocol (DHCP) server? Media Access Control address; A MAC address is a hardware address assigned to a device by the manufacturer. A Virtual Private Network (VPN) uses a particular layer from the OSI reference model to carry an encrypted payload that actually contains an entire second set of packets. Which layer is used? Transport; The payload section of the transport layer is used to contain an entire second set of packets. What service acts on behalf of a client in order to access another service? Proxy Server; Proxies sit between clients and other servers to facilitate connections. During the name resolution process, which technique is used to avoid congestion when querying a server? Anycast; Anycast allows a request to be sent to an appropriate server based on factors, like location. This helps relieve severe congestion.