# 4.7. Volume accounting

## 4.7.1. What is volume accounting?

It basically means to count the number of bytes transmitted from or to the Internet. kppp can count incoming bytes, outgoing bytes or both. Itīs up to you what you want (or must) use.

## 4.7.2. Why should I use volume accounting?

Because nowadays, many Internet Service Providers begin to bill their customers depending on the number of bytes transferred. Or very often those ISP give you an arbitrary transfer limit, and charge you for every megabyte above this limit. kppp shows you your current volume and can help you keeping your bills to the minimum. Of course, if you do not have volume limits and you are curious, you can use it too...

## 4.7.3. What type of volume accounting should I select?

That depends on your provider. Many of them only count how many megabytes you get from Internet and ignore how much you send. In that case you should choose "Bytes in". If you have to pay for both you should select "Bytes in and out". "Bytes out" is not of much use and is only here for completeness.

## 4.7.4. Drawbacks

Unfortunately thereīs a drawback on volume accounting. kppp will just count the number of bytes regardless their origin. Many providers set their limit only for internet access, not for their own network. So, if you do a little web surfing and you use a proxy-cache, the proxy will reside inside the network of your provider and he will not charge you for bytes transferred from his proxy cache. However, kppp will not know that these IP packets are coming from the proxy and thus count them. So, if you use a proxy, or your provider uses a caching news server (like nntpcached), the volume reported by kppp may be higher.