The SocketTools ActiveX Edition includes components that implement
fourteen standard Internet application protocols, as well as libraries
which provide support for general TCP/IP networking services, encoding
and compressing files, processing email messages and ANSI terminal
emulation. The following controls are included in the SocketTools
ActiveX Edition:
Domain Name Service Control
The Domain Name Service (DNS) protocol is what applications use to
resolve domain names into Internet addresses, as well as provide
other information about a domain, such as the name of the mail
servers which are responsible for receiving email for users in that
domain. The DNS control enables an application to query one or more
nameservers directly, without depending on the configuration of the
client system.
File Encoding Control
The File Encoding control provides methods for encoding and decoding
binary files, typically attachments to email messages. The process
of encoding converts the contents of a binary file to printable text.
Decoding reverses the process, converting a previously encoded text
file back into a binary file. The control supports a number of
different encoding methods, including support for the base64, uucode,
quoted-printable and yEnc algorithms. The control can also be used to
compress and expand data in a user-supplied buffer or in a file.
File Transfer Protocol Control
The File Transfer Protocol (FTP) control provides methods for
uploading and downloading files from a server, as well as a
variety of remote file management methods. In addition to file
transfers, an application can create, rename and delete files and
directories, list files and search for files using wildcards. The
control provides both high level methods, such as the ability to
transfer multiple files in a single method call, as well as access to
lower level remote file I/O methods.
Hypertext Transfer Protocol Control
The Hypertext Transfer Protocol (HTTP) control provides an interface
for accessing documents and other types of files on a server. In some
ways it is similar to the File Transfer Protocol in that it can be
used to upload and download files; however, the protocol has expanded
to also support remote file management, script execution and
distributed authoring over the World Wide Web. The SocketTools
Hypertext Transfer Protocol control implements version 0.9, 1.0 and
1.1 of the protocol, including features such as support for proxy
servers, persistent connections, user-defined header fields and
chunked data.
Internet Control Message Protocol Control
The Internet Control Message Protocol (ICMP) is commonly used to
determine if a server is reachable and how packets of data are
routed to that system. Users are most familiar with this protocol as
it is implemented in the ping and tracert command line utilities. The
ping command is used to check if a system is reachable and the amount
of time that it takes for a packet of data to make a round trip from
the local system, to the server and then back again. The tracert
command is used to trace the route that a packet of data takes from
the local system to the server, and can be used to identify
potential problems with overall throughput and latency. The control
can be used to build in this type of functionality in your own
applications, giving you the ability to send and receive ICMP echo
datagrams in order to perform your own analysis.
Internet Message Access Protocol Control
The Internet Message Access Protocol (IMAP) is an application
protocol which is used to access a user's email messages which are
stored on a mail server. However, unlike the Post Office Protocol
(POP) where messages are downloaded and processed on the local
system, the messages on an IMAP server are retained on the server and
processed remotely. This is ideal for users who need access to a
centralized store of messages or have limited bandwidth. For example,
traveling salesmen who have notebook computers or mobile users on a
wireless network would be ideal candidates for using IMAP. The
SocketTools IMAP control implements the current standard for this
protocol, and provides methods to retrieve messages, or just certain
parts of a message, create and manage mailboxes, search for specific
messages based on certain criteria and so on. The interface is
designed as a superset of the Post Office Protocol interface, so
developers who are used to working with the POP3 control will find
the IMAP control very easy to integrate into an existing
application.
Internet Server Control
The Internet Server control provides a simplified interface
for creating event-driven, multithreaded server applications using
the TCP/IP protocol. The control interface is similar to the
SocketWrench ActiveX control, however it is designed specifically to
make it easier to implement a server application without requiring
the need to manage multiple socket controls. In addition, the
Internet Server control supports secure communications using the
Secure Sockets Layer (SSL) and Transport Layer Security (TLS)
protocols.
Mail Message Control
The Mail Message control provides an interface for composing and
processing email messages and newsgroup articles which are
structured according to the Multipurpose Internet Mail Extensions
(MIME) standard. Using this control, an application can easily create
complex messages which include multiple alternative content types,
such as plain text and styled HTML text, file attachments and
customized headers. It is not required that the developer understand
the complex MIME standard; a single method call can be used to create
multipart message, complete with a styled HTML text body and support
for international character sets. The Mail Message control can be
easily integrated with the other mail related protocol libraries,
making it extremely easy to create and process MIME formatted
messages.
Network News Transfer Protocol Control
The Network News Transfer Protocol (NNTP) control is used with servers that
provide news services. This is similar in functionality to bulletin
boards or message boards, where topics are organized hierarchically
into groups, called newsgroups. Users can browse and search for
messages, called news articles, which have been posted by other
users. On many servers, they can also post their own articles which
can be read by others. The largest collection of public newsgroups
available is called USENET, a world-wide distributed discussion
system. In addition, there are a large number of smaller news
servers. For example, Microsoft operates a news server which
functions as a forum for technical questions and announcements. The
SocketTools control provides a comprehensive interface for accessing
newsgroups, retrieving articles and posting new articles. In
combination with the Mail Message control to process the news
articles, SocketTools can be used to integrate newsgroup access with
an existing email application, or you can implement your own
full-featured newsgroup client.
News Feed Control
The News Feed control
enables an application to download and process a syndicated news feed
in in standard RSS format. News feeds can be accessed remotely from a
web server, or locally as an XML formatted text file. The source of
the feed is determined by the URI scheme that is specified. If the
http or https scheme is specified, then the feed is retrieved from a
web server. If the file scheme is used, the feed is considered to be
local and is accessed from the disk or local network. The News Feed
control provides an interface that enables you to open a feed by URL
and iterate through each of the items in the feed or search for a
specific feed item. The control also provides a method that can be
used to parse a string that contains XML data in RSS format, where the
feed may have been retrieved from other sources such as a database.
Post Office Protocol Control
The Post Office Protocol (POP) control provides access to a user's new email
messages on a mail server. Methods are provided for listing available
messages and then retrieving those messages, storing them either in
files or in memory. Once a user's messages have been downloaded to
the local system, they are typically removed from the server. This is
the most popular email protocol used by Internet Service Providers
(ISPs) and the SocketTools control provides a complete interface for
managing a user's mailbox. This control is typically used in
conjunction with the Mail Message control, which is used to process
the messages that are retrieved from the server.
Remote Access Services Control
The Remote Access Services (RAS) control enables an application to
connect to an Internet Service Provider (ISP) using a standard
Dial-Up Networking connection. Using this control, the application
can discover what dial-up devices are available, what dial-up
networking entries, known as "connectoids", are available
on the local system and allows the program to manage those
connections. Existing connections can be monitored, new connections
created and a single control can be used to manage multiple dial-up
connections if the system has more than one modem. While Windows can
be configured to simply autodial a service provider whenever a
network connection is needed, this component gives your application
complete control over the process of connecting to a service
provider, monitoring that connection and then terminating that
connection if needed.
Remote Command Protocol Control
The Remote Command protocol is used to execute a command on a server
and return the output of that command to the client. The SocketTools
control provides an interface to this protocol, enabling applications
to remotely execute a command and process the output. This is most
commonly used with UNIX based servers, although there are
implementations of remote command servers for the Windows operating
system. The SocketTools control supports both the rcmd and rshell
remote execution protocols and provides methods which can be used to
search the data stream for specific sequences of characters. This
makes it extremely easy to write Windows applications which serve as
light-weight client interfaces to commands being executed on a UNIX
server or another Windows system. The control can also be used to
establish a remote terminal session using the rlogin protocol, which
is similar to how the Telnet protocol methods.
Secure Shell Protocol Control
The Secure Shell (SSH) protocol is used to establish a secure
connection with a server which provides a virtual terminal session
for a user. Its functionality is similar to how character based
consoles and serial terminals work, enabling a user to login to the
server, execute commands and interact with applications running on
the server. The SSH control provides an interface for
establishing the connection and handling the standard I/O functions
needed by the program. The control also provides methods that enable
a program to easily scan the data stream for specific sequences of
characters, making it very simple to write light-weight client
interfaces to applications running on the server.
Simple Mail Transfer Protocol Control
The Simple Mail Transfer Protocol (SMTP) enables applications to
deliver email messages to one or more recipients. The control
provides an interface for addressing and delivering messages, and
extended features such as user authentication and delivery status
notification. Unlike Microsoft's Messaging API (MAPI) or
Collaboration Data Objects (CDO), there is no requirement to have
certain third-party email applications installed or specific types
of servers installed on the local system. The SocketTools control can
be used to deliver mail through a wide variety of systems, from
standard UNIX based mail servers to Windows systems running Exchange
or Lotus Notes and Domino. Using the SocketTools control, messages
can be delivered directly to the recipient, or they can be routed
through a relay server, such as an Internet Service Provider's mail
system. The Mail Message control can be integrated with this control
in order to provide an extremely simple, yet flexible interface for
composing and delivering mail messages.
SocketWrench Control
The SocketWrench control provides a higher-level interface to the
Windows Sockets API, designed to be suitable for programming
languages other than C and C++. In addition, SocketWrench supports
secure communications using the Secure Sockets Layer (SSL) and
Transport Layer Security (TLS) protocols.
Telnet Protocol Control
The Telnet protocol is used to establish a connection with a server
which provides a virtual terminal session for a user. Its
functionality is similar to how character based consoles and serial
terminals work, enabling a user to login to the server, execute
commands and interact with applications running on the server.
The Telnet control provides an interface for establishing the
connection, negotiating certain options (such as whether characters
will be echoed back to the client) and handling the standard I/O
functions needed by the program. The control also provides methods
that enable a program to easily scan the data stream for specific
sequences of characters, making it very simple to write light-weight
client interfaces to applications running on the server. This control
can be combined with the Terminal Emulation control to provide
complete terminal emulation services for a standard ANSI or DEC-VT220
terminal.
Terminal Emulation Control
The Terminal Emulation control provides a comprehensive interface for
emulating an ANSI or DEC-VT220 character terminal, with full support
for all standard escape and control sequences, color mapping and
other advanced features. The control methods provide both a high
level interface for parsing escape sequences and updating a display,
as well as lower level primitives for directly managing the virtual
display, such as controlling the individual display cells, moving the
cursor position and specifying display attributes. This control can
be used in conjunction with the Remote Command or Telnet Protocol
control to provide terminal emulation services for an application, or
it can be used independently. For example, this control could also be
used to provide emulation services for a program that provides serial
modem connections to a server.
Text Message Control
The Text Message
control enables applications to send text messages to mobile devices.
It provides an interface that can be used to obtain information about
the wireless service provider that is associated with the phone number
for a smartphone or other mobile device, and can send a message with a
single method call. Messages can be delivered directly to the service
provider's gateway, or can be relayed through a local mail server.
With this control, an application can send text message alerts when
certain conditions occur (such as an error) or as a notification
mechanism that's used in addition standard email messages.
Time Protocol Control
The Time Protocol control provides an interface for synchronizing the
local system's time and date with that of a server. The
control enables developers to query a server for the current time and
then update the system clock if desired.
Web Location Control
The Web Location control provides geographical information about the
physical location of the computer system based on its external IP
address. This can enable developers to know where their application is
being used, and provide convenience functionality such as
automatically completing a form based on the location of the user.
Web Storage Control
The Web Storage control provides private cloud storage for uploading and
downloading shared data files which are available to your application.
This is primarily intended for use by developers to store configuration
information and other data generated by the application. For example,
you may want to store certain application settings, and the next time
a user or organization installs your software, those settings can be
downloaded and restored.
Whois Protocol Control
The Whois protocol control provides an interface for requesting
information about an Internet domain name. When a domain name is
registered, the organization that registers the domain must provide
certain contact information along with technical information such as
the primary name servers for that domain. The Whois protocol enables
an application to query a server which provides that registration
information. The SocketTools control provides an interface for
requesting that information and returning it to the program so that
it can be displayed or processed.