1 07, 2015

How does SSH work – part three

SSH-2 uses a layered architecture, consisting of a transport layer, a user authentication layer, and a connection layer (described here).

The previous post in this series explained the transport layer, which provides encryption, host authentication and integrity checking. Encryption and integrity checking ensure that messages sent between client and server cannot be viewed or tampered with. Host authentication means that the client knows it is communicating with the right server.

The next step is for the client to […]

25 06, 2015

Why use CompleteFTP’s Enterprise Edition?

CompleteFTP, our popular secure FTP server,  comes in three editions – Standard, Professional and Enterprise.

The Standard Edition is for those who want the essential features of FTP, FTPS and SFTP for the lowest possible price.

The Professional Edition supports all standard protocols such as FTP, FTPS, SFTP, SCP, HTTP and HTTPS. It supports Windows domain users, event notifications and process triggers, quotas, SSH terminal access and advanced file permissions, as well as […]

22 06, 2015

How does SSH work – part two

The previous post in this series described how the SSH-2 protocol uses a layered architecture, consisting of a transport layer, a user authentication layer, and a connection layer.  This post will explain the main features of the transport layer.

The transport layer is message-based, and provides encryption, host authentication and integrity checking. Messages are sent between client and server over TCP/IP via the binary packet protocol – “packets” of data are exchanged in the format defined below, and the […]

6 06, 2015

How does SSH work – part one

SSH History

In the late 1980’s and 1990’s, network tools such as rlogin and telnet were commonly used for logins into remote machines, typically on Unix platforms. These tools allowed users to open command shells that permitted them to execute commands on the remote machines as if they were actually on the machine, and were extremely useful for systems administration.

There was one critical drawback – none of these tools were secure. Passwords were sent over networks in plaintext, meaning anyone […]

28 05, 2015

How does SSL/TLS work – part four

Previous posts in this series have covered the SSL/TLS protocol in some detail. Now it’s time to examine some of the more recent vulnerabilities that have been found, and how they were (and can be) dealt with.

Heartbleed

Heartbleed is one of the most serious vulnerabilities ever found in SSL/TLS, allowing the theft of server keys, user session ids and user passwords from compromised systems. It was not, however, an SSL protocol flaw, but rather […]

16 05, 2015

CompleteFTP scheduled events

Up until 8.3.0, CompleteFTP’s process triggers were initiated by certain events occurring in the server, such as users logging in or out, or files being uploaded or downloaded. Process triggers could launch a batch, Powershell or FTP script, or an executable.

Over time it became obvious from customer feedback that users also wanted to be able to initiate scripts independently from server events – they wanted the power of cron to schedule scripts at whatever time […]