Websocket head-of-line blocking

1. What is head of the line blocking problem?
2. Which mechanism in TCP causes head of line blocking in HTTP 2?
3. What is WebSockets header size?
4. What is head of line blocking does it occur in input ports or output ports?
5. What happens if I block on line?
6. How do you know if they block you on line?
7. What is the TCP mechanism used to avoid congestion?
8. What mechanisms does TCP use to avoid network congestion?
9. What is head of line blocking problem in HTTP 1?
10. Can WebSockets have headers?
11. Can WebSockets be blocked?
12. Do WebSockets support headers?
13. What is head of line blocking TCP?
14. What is blocking problem?
15. What is per line blocking?
16. How do I unblock my line ID?
17. Should I disable port blocking?
18. Should I have port blocking on or off?
19. What is TCP header used for?

What is head of the line blocking problem?

Head-of-line (HoL) blocking occurs if there is a single queue of data packets waiting to be transmitted, and the packet at the head of the queue (line) cannot move forward due to congestion, even if other packets behind this one could.

Which mechanism in TCP causes head of line blocking in HTTP 2?

This allows HTTP/1.1 to somewhat mitigate not only the HTTP-level but also the TCP-level HOL blocking. As such, in some cases, HTTP/2 on a single connection has a hard time being faster than or even as fast as HTTP/1.1 on 6 connections. This is mainly due to TCP's “congestion control” mechanism.

What is WebSockets header size?

The smallest valid full WebSocket message is two bytes, such as this close message sent from the server with no payload: 138, 0 . Yet the longest possible header is 14 bytes, which would represent a message sent from the client to the server with a payload greater then 64KB.

What is head of line blocking does it occur in input ports or output ports?

Does it occur in input ports or output ports? HOL blocking – a queued packet in an input queue must wait for transfer through the fabric because it is blocked by another packet at the head of the line. It occurs at the input port.

What happens if I block on line?

When you block an account on LINE: You'll no longer be able to receive messages from that account. It will appear in Blocked accounts instead of your friend list. Blocking an account doesn't completely remove it as a friend or friend recommendation.

How do you know if they block you on line?

Try to chat with them. The first thing how to know if you have been blocked on LINE is by trying to chat with them. If you are blocked on LINE, the characteristic feature is that chat messages are not read.

What is the TCP mechanism used to avoid congestion?

To avoid congestion, TCP utilizes a multi-faceted strategy. For all connections in the network, TCP creates a congestion window (CWND) that helps in limiting the number of total packets that are unacknowledged and may be in transit. This mechanism used by TCP to avoid congestion is called the sliding window.

What mechanisms does TCP use to avoid network congestion?

Transmission Control Protocol (TCP) uses a network congestion-avoidance algorithm that includes various aspects of an additive increase/multiplicative decrease (AIMD) scheme, along with other schemes including slow start and congestion window (CWND), to achieve congestion avoidance.

What is head of line blocking problem in HTTP 1?

Head of Line blocking in HTTP terms is often referring to the fact that each browser/client has a limited number of connections to a server and doing a new request over one of those connections has to wait for others to complete the process. So the head of line requests blocks the subsequent ones.

Can WebSockets have headers?

Unfortunately, it doesn't work because the WebSocket API doesn't support setting custom headers.

Can WebSockets be blocked?

These are the so-called Websocket connections (more information at the bottom of this article). A blocked connection can be caused by: AdBlocker / Cookie blocker browser extensions. Antivirus and Firewall software.

Do WebSockets support headers?

Note that the WebSockets protocol itself supports custom headers since it starts with a HTTP handshake similar to a normal HTTP request. It is only the browser API which is missing the ability to use custom headers.

What is head of line blocking TCP?

Head of Line blocking (in HTTP/1.1 terms) is often referring to the fact that each client has a limited number of TCP connections to a server (usually 6 connections per hostname) and doing a new request over one of those connections has to wait for the previous request on the same connection to complete before the ...

What is blocking problem?

Blocking occurs when a process has acquired lock on a set of rows, and another process is trying to acquire a lock on the same set of rows. In such a case, the other process has to wait until the first process finishes its job and releases the lock on the above said rows.

What is per line blocking?

Caller ID Per Line Blocking prevents your name and number from permanently displaying.

How do I unblock my line ID?

After that, LINE will automatically display the so-called "manage friends." In "manage friends" you can see two options, namely hidden users and blocked users. Well, you can choose "unblock users" then. After that, you will be shown a list of friends that you have hidden.

Should I disable port blocking?

Port blocking can complicate application design and development and create uncertainty about whether applications will function properly when they are deployed. Port blocking can also cause applications to not function properly or “break” by preventing applications from using the ports they were designed to use.

Should I have port blocking on or off?

ISPs should avoid port blocking unless they have no reasonable alternatives available for preventing unwanted traffic and protecting users. Further, if port blocking is deemed necessary, it should only be used for the purposes of protecting the implementing ISP's network and users.

What is TCP header used for?

The Transmission Control Protocol (TCP) header is the first 24 bytes of a TCP segment that contains the parameters and state of an end-to-end TCP socket. The TCP header tracks the state of communication between two TCP endpoints.