What does a proxy cache do when it has a fresh copy of the requested object?

Returns the stored copy without contacting the origin

Forwards the request to the origin anyway

Redirects the client to the nearest CDN

How does a CDN direct a user to a suitable server?

Its DNS directs the user to the nearest or least-loaded edge server

The user must pick a server manually

The browser caches every site locally

The origin server forwards all traffic itself

Who installs a forward proxy, compared with a CDN?

Forward proxy by the user's organisation for its own users; CDN by or for the content owner for its customers' content

Forward proxy by the content owner; CDN by the user's organisation

Both are installed by the user's ISP only

Both are installed by the content owner

Which description fits a reverse proxy?

A server-side node that caches, balances load and terminates SSL, like a one-site CDN node

A server at the client side that filters outgoing requests

A DNS server that rotates addresses

2071 Bhadra · 4 marks

Short note: Proxy CDN

Short answer

A proxy server is a user-side cache reducing bandwidth and latency for outgoing requests. A CDN is a globally distributed system of edge servers that replicates content and directs users to the nearest node via DNS, improving speed and offloading origin servers.

Write a short note on Proxy CDN.

A proxy server (web cache) is an intermediate server between clients and origin web servers. Clients are configured to send their HTTP requests to the proxy; if it has a fresh copy it returns it, otherwise it fetches the object from the origin, stores a copy and returns it. Benefits: shorter response time, less Internet bandwidth, lower load on origin servers, plus access control, content filtering and logging. Freshness is checked with conditional GET. Examples: Squid, Microsoft ISA/TMG.

A Content Distribution Network (CDN) is a network of geographically spread servers that replicate the content of content providers close to users (Akamai, Cloudflare). The CDN's DNS directs each user to the nearest or least-loaded edge server, so objects arrive faster and the origin server is protected from overload.

 Users --> [Proxy cache] --> Internet --> [CDN edge] --> Origin
           (user side:                    (content side)
            inside ISP/company)

Difference in position

A forward proxy is installed by the user's organisation and is shared by its own users for all sites.
A CDN is installed by (or for) the content owner and serves only its customers' content, to everyone.

A reverse proxy at the server side works like a one-site CDN node: it caches, balances load and terminates SSL for the origin servers.

✓ Answer checked by Claude Opus 5.5 (high effort)

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