Some random A-Level Computing questions
Hey, i have some A-Level computing past exam papers and i was wondering if someone would mind having a go at answering the questions i cannot do. The teacher has said he doesnt mind how we get the answers so dont worry, i am not cheating :p Anyway, here goes:
1. Why is hardware and software CODEC preferred to the software only CODEC?
2. Why must a CODEC be used if a movie from a video caera is to be stored on DVD-R?
3. What purpose might a Digital Linear Tape be used for?
4. Give two advantages to a company on using a value-added network?
5. Describe the difference between and ISP and an On-line Service Provider
6. Describe the difference between Usenet and Internet Relay Chat
Think thats all, i can do the other ones that i've got. If anyone knows the answer to any of the above questions. Please post or at least give a hint.
Thanks
BIOSTALL
Re: Some random A-Level Computing questions
Here is #6
Quote:
(should help with a few others, too.
http://www.chaminade.org/MIS/internet.htm)
Usenet Newsgroups
Unlike e-mail which is usually one-to-one, a Usenet newsgroup may have thousands of readers. Using a newsgroup is much like posting messages on a bulletin board. You can also think of a newsgroup as an international discussion group that focuses on a specific topic. Examples of topics include computers (comp), hobbies/games/recreation (rec), and educational subjects for students and teachers (k12). To join a newsgroup you need to subscribe to it. Articles are displayed with a subject line and then you can click to read those of interest. You can reply to an article or send a new one of your own, called posting. Most web browsers allow you access to newsgroups.
Internet Relay Chat (IRC)
Internet Relay Chat, or IRC, is a conversation system that allows you to chat in real live time with people all over the world (unlike e-mail, which is delayed). The only difference between IRC and a phone conversation is that you need to type your message. Some ISPs such as America Online also allow you to chat, but only with other AOL subscribers. AOL allows you to choose a "room" of interest such as special interests, news, sports, and places before joining the chat.
Re: Some random A-Level Computing questions
Quote:
Why is hardware and software CODEC preferred to the software only CODEC?
a hardware software hybrid would allow for faster encoding/decoding and flexiblity(algorithim tweaks/errors). A software only-codec would generally be slower than a hardware codec but a hardware only codec wouldnt be very flexible with changes/enhancements to the method.
Quote:
Why must a CODEC be used if a movie from a video caera is to be stored on DVD-R
If the dvd is intended for use in a dvd player, most dvd players can only decode Mpeg1/Mpeg2 encoded videos.
Another reason would be that dvd-r's have a limited storage capacity. Using a codec you can fit (compress) more video on a single disc with minmal quality losses.
ISP vs OSP
ISP - (Internet Service Providers) - Allow you to connect to their network to access the internet.
OSP - (Online Service Providers) - Provide the same service an ISP provides but also provides you with additional services that are only provided to customers (AOL is an example of an OSP)
DLT - (Digital Linear Tape) - http://searchstorage.techtarget.com/...759350,00.html
Value Added Network - http://searchnetworking.techtarget.c...341986,00.html
Advantages: Security, since the data is traveling over a network that is private, there is less of a chance of sensitive information falling into the wrong hands.
This network is managed by professionals and since you are paying them, it is their responsibily to make sure everything works. (its nice to have someone to point your finger at :P)
