Question

Suppose, in the other direction, we abandon any pretense at all of DNS hierarchy, and simply move all the .com entries to the root name server: www.cisco.com would become www.cisco, or perhaps just cisco. How would this affect root name server traffic in general? How would this affect such traffic for the specific case of resolving a name like cisco into a Web server address?

Short answer

Root name server traffic would increase substantially, risking overload and higher latency. Specific name resolutions like 'cisco' would also be slower due to direct handling by the root server.

Step-by-step solution

Understand the Domain Name System (DNS) Hierarchy

First, recognize that DNS hierarchy involves multiple levels: the root, top-level domains (TLDs) like .com, second-level domains like cisco, and individual hostnames like www. DNS servers manage these levels, distributing the load.

Identify the Current Role of Root Name Servers

Root name servers currently direct queries to appropriate TLD name servers, which then direct to further specific subdomains. They handle only the first step in the query process.

Consider the Impact of Moving .com Entries to Root

If all .com entries are managed by the root name server, that server would receive significantly more traffic. Instead of handling queries to direct towards a TLD, it would have to manage a vast number of second-level domain names directly.

Evaluate General Traffic Increase

Overall, root name server traffic would increase dramatically because it would have to handle all queries that were previously directed to .com TLD servers. This could lead to higher latency and potential system overload.

Assess Specific Case: Resolving 'cisco'

For resolving a name like 'cisco' into a Web server address, the root server would have to respond to every request directly, rather than having the load distributed to lower-level DNS servers. This would similarly increase query traffic for specific names and could slow down the response time.

Key concepts

Root name servers

Root name servers are the top-most servers in the Domain Name System (DNS) hierarchy. They don't handle the entire web traffic but play a critical role. Their job is to direct a query to the correct Top-Level Domain (TLD) server. Think of them like a GPS guide pointing you the right way when you ask for something general. For example, if you are looking for a website ending in '.com', the root name servers will point you to the TLD servers responsible for '.com'. But if you transfer all '.com' entries to root name servers, it increases their traffic tremendously. They would then handle more specific queries that are usually managed by lower-level servers.

Domain Name System (DNS)

DNS is like the phonebook of the internet. It translates human-friendly domain names like www.cisco.com into IP addresses that computers use to identify each other on the network.
The DNS hierarchy involves different levels:

• Root level
• Top-Level Domains (TLD) like .com, .org, .net
• Second-level domains like 'cisco' in cisco.com
• Finally, hostnames like 'www' in www.cisco.com

Each of these levels helps distribute the load, making the internet faster and more efficient. If you eliminate the hierarchy and move everything to the root, you would overload the system.

TLD servers

Top-level domain (TLD) servers manage top-level domain names. For example, TLD servers for '.com' handle all queries for domains ending in '.com'. When a root server directs a query to a TLD server, the TLD server will then point to the next relevant DNS server for that domain.

Moving all '.com' data to root name servers would remove the TLD layer and give much of that workload directly to the root servers. This would lead to slower responses and higher traffic, with root name servers handling millions of additional queries. It would compromise the DNS's efficiency and reliability.

Web server address resolution

Web server address resolution is the process of mapping a domain name to its corresponding IP address. When you type a URL like www.cisco.com into your browser, the DNS works like a detective, finding the correct IP address. Following the DNS hierarchy, a request starts at the root name server and moves downwards.

If root servers had to resolve all queries (like finding the IP address of 'cisco'), the process would slow down due to the traffic overload. Every request would take longer to fulfill, making the internet slower for everyone. Distribution of tasks among different levels of DNS servers keeps the system fast and efficient.