6 ms·
The first example is more likely congestion than throttling, but that's only really a difference in the manner that your ISP is being cheap (and not having enou
by mcpherrinm 8y ago
The first example is more likely congestion than throttling, but that's only really a difference in the manner that your ISP is being cheap (and not having enough bandwidth upstream).
Using a VPN in this case is probably causing your traffic to take a different route than everyone else's youtube traffic, thus avoiding the congestion bottleneck.
Netflix may have a local cache nearer to you, so you don't hit the congestion (and the amount of content in a Netflix cache is probably a lot less than Youtube).
Example 2 could be a packet-lossy network which causes your TCP connection to ramp back. If it's constant packet loss, your TCP connection will probably get slower and slower: TCP uses packet loss as a signal it's going too fast, but if that's not the cause of the loss, your connection will just keep getting slower.
- criddell 8y ago> but that's only really a difference in the manner that your ISP is being cheap Doesn't that depend on the peering agreements? How do you know it isn't the case that problem at the links isn't due to the video service paying for insufficient bandwidth?
- mcpherrinm 8y agoWhere the bottleneck exists is difficult to pinpoint, for sure. Especially just based on a vague description. I'm making some assumptions.
- Timmah 8y agoIsn't TCP a lossless protocol? I thought it ended the session if the packets were dropped. Edit: downvoted for asking a question. Thanks reddit.
- EpicEng 8y agoPackets can be dropped and TCP will retry (among other things; packet loss is a hueristic.) It won't just cut the session on some amount of packet loss, that would lead to constant failures.
- mcpherrinm 8y agoWhenever you send a packet in TCP, the recipient sends back an "ACK" packet confirming receipt. If some timeout interval passes, the packet will be sent again. This means that some packet loss will not interfere with a TCP connection. This is used for congestion control: Imagine you have a computer with a 1gbps LAN hooked up to a 100mbps network. You can send packets at 1gpbs over the LAN, but 90% of them would be dropped at the speed change point. The TCP stack will notice it is losing packets, and will throttle itself accordingly. TCP is actually more complicated than just this, but this is one of the more important parts.