Forum Discussion

d3x0r's avatar
New Contributor

Datacap is not Data, but Packets!

I started monitoring bytes input and bytes output on my router. 

Yesterday Cox reports I used 40GB  while my router shows 23,997,300,432  input+output bytes.

However, received packets 20151773  and transmitted packets 6875659  (27,027,432 total)

so 40GB / 27M packets = 1479.   That means you're going to charge me based on packet count and not actual data usage.

That means all these 46 byte packets that I'm receiving from your equipment is going to be

190,876,435,200 used per month by just being on your network and receiving packets that I didn't use. and a minimum of 6,362,547,840 per day.  

If you're going to limit us based on packets, you should express it in terms of packet counts and not data at least.

But you also should not count the broadcast arps that we all receive from your equipment probing your own network.

4 Replies

Replies have been turned off for this discussion
  • d3x0r's avatar
    New Contributor

    I also have a lot of probes of my IP from outside sources that result in block rules on the firewall.  I'm getting charged for all those packets I have dropped too?  Packets that go nowhere?

    Someone could send a bunch of 0 byte packets at me that don't actually have to enter my network and I'd get over usage charges?

  • d3x0r's avatar
    New Contributor

    And on futher consideration, a simple ack for recieving a stream means I'm using 2x the bandwidth even though there's 0 bytes of data transferred (yes there is 80 bytes of data in protocol) but since almost every packet sent is acknowledged the calculation of packets * bytes should be /2.    I was just watching for a while... which I thought was what was killing my bandwidth usage, 

    but realized that I've received 9,905,966,729 bytes so far today, but by packets that's 17,211,888,936; and realized that at a 2:1 ratio, that's obviously because traffic received is acknowledged.

    I also do a lot of work on remote systems using ssh; this means that every key stroke (1 byte packets basically) I'm getting marked for usage of 17x the data actually used. (for that I did include TCP/IP header bytes for 81, not just 1)

  • ItsRushTime's avatar
    New Contributor
    your math and logic are really confusing to me.. Your 23,997,300,432 bytes should equal 23.9 GBytes. That is what you should be disputing.. How did you jump to the 40GB/Divided by Packets? What is the significance of the 1479 number?
  • cwb3106's avatar
    New Contributor

    An Internet packet can vary in size. The max size depends on a variety of factors, but is typically around 1,500 bytes. I think d3x0r is suggesting that the Cox data meter is assuming every packet is the max size. Since a lot of Internet packets are quite small (less than 100 bytes), this round up would cause the data meter to greatly overstate the usage.

    To support this suggestion, d3x0r divided the reported (by Cox) usage (40 GB) by the reported (by his router) number of packets sent/received (27,027,432) to come up with an average packet size of 1479. That's in the range of typical packet size maximums.

    FWIW, 23,997,300,432 bytes is 22.35GB. In most computer contexts, 1K is 1024 (not 1000) and 1G is  1,073,741,824. Confusing, but that's the way it's done. Using that same correction, the 40GB that the data meter reports is (about)  42,949,672,960 bytes which raises the average packet size to (about) 1,589 bytes.

    At least, this is how I interpreted d3x0r's posts.