Results for "port 443"

The same protocol on both ports, and a handshake in front of one of them. Here is what that changes, why the old port stays open anyway, and the firewall rule almost everyone gets wrong.

Every application configuration field defaults to 389, and almost none of them should be using it. The choice is two questions, and collapsing them into one is where the confusion starts.

A network firewall stops at the address. A WAF opens the request and reads what is inside it, which is the only way to see an attack aimed at the application. Here is what that catches, what it never will, and the deploy...

Twenty bytes carry everything that turns an unreliable network into an ordered byte stream. Four of the fields answer most of the questions anybody asks of a capture.

Two products sold under one name, one of which grants three applications and the other the whole network. And an appliance on the public internet that has to be patched before anything else you run.

Nearly every firewall a business can buy is stateful, so this is not a purchase decision. It is a question of where you are writing rules, and what state costs when routing or load goes wrong.

Rules matched in order, a table of connections already allowed, and a default that denies the rest. Here is how a packet is actually judged, what a firewall reliably stops, and the four things it does not touch.

Almost every argument about which VPN protocol is more secure turns out to be an argument about which job is being discussed. Name the job first and most of the comparison answers itself.

The two use the same mechanism and serve opposite sides. A small business rarely runs a forward proxy anymore, but everything it publishes on the web sits behind a reverse proxy somewhere.

Thousands of packets, and the answer is in about six of them. The filters that get you there, the handshake signatures that name the cause, and the coloring rules worth trusting.

Everyone gets the number and stops there. The useful part is the second port: a gateway presents TLS on 443 and reaches the hosts on 3389 from inside, so nothing on the internet ever speaks to the RDP port at all.

Sixteen bits in a header, and an agreement about what they mean. Here is what a port actually is, why nothing is physically opened or closed, and why a single server holds fifty thousand connections on one of them.

Every lookup goes out over UDP and some of them come back saying try again with TCP. Here is when that happens, why it happens more than it used to, and the firewall rule most networks get half right.

One port carrying four things, and a piece of advice that dominates every search result for it while doing almost nothing. Here is what runs there and what actually secures it.

Nothing on a Windows network works without this port, and the two ways it goes wrong are a firewall rule that permits only UDP and a clock that has drifted five minutes.

This is the only common Windows port that is a directory rather than a service, which is why a firewall rule that permits it and nothing else fails in a way nobody expects.

Commands go over port 21 and files do not. That split is why FTP breaks through firewalls and NAT when nothing else does, and why the fix is a mode rather than a rule.

A registered port with nothing on it is the kind of number a tool adopts as a default. It is also the kind of number that makes an alert almost binary, which is rare and cheap.

The cleartext mail port, defined by a standard from 1996 that is still current and still candid about its own weaknesses. The behavior to understand first is that nothing is deleted until the client says QUIT.

Port 1433 is the answer to the question and rarely the answer to the problem. Named instances, the Browser service, the admin connection and Azure SQL each put a SQL Server connection somewhere else.