The following sections provide an overview of the IP phone support provided by the Cisco Content Transformation Engine (CTE) 1400 Series and the Design Studio application:
Note The CTE supports IP phones that are compatible with Cisco IP phone XML
objects, such as the Cisco 7940 and 7960 IP Telephones and the PolyCom
SoundPoint 500CS, as well as IP phones that support HTML.
Introduction
The CTE enables you to deliver web applications in the format and presentation appropriate for IP phones. The CTE provides a wide range of default transformations so that web applications work without additional development effort. You can, however, use Design Studio or XHTML extensions to further refine the default transformations.
The following sections describe the transformations provided by the CTE, Design Studio, and XHTML extensions:
By default, the CTE transforms web applications as follows:
Converts the data into XML, using Cisco XML extensions.
Converts the data to the 7-bit ASCII encoding supported by IP phones.
Divides a web page into screens (cards) and adds the appropriate navigation Soft Keys.
Prepends the CTE IP address to links so that web application requests are directed through the appliance.
Converts a href elements into numbered links so that a user can select a link by using the keypad.
Enables clickable images and follows links.
Strips items that are not supported by IP phones, such as images that are larger than 20 pixels in both width and height.
Converts special characters in URLs to HTML character entity references.
Converts special characters in text to decimal character references.
Converts input and textarea elements into the Cisco IP phone XML object CiscoIPPhoneInput, with a default InputFlags value of ASCII.
Supports audio that is 8-bit G.711 Mu-Law audio codecs sampled at 8 kHz.
Transformations Available Through Design Studio or CTE XHTML Extensions
Web applications designed for a desktop browser usually contain more items than are appropriate for use on an IP phone. You can use Design Studio or XHTML extensions to refine a default transformation further, as follows:
Use Design Studio, a PC-based application, to specify how you want a web application to appear when delivered to IP phones.
Use the Design Studio point-and-click interface to select the items that are to appear on IP phones and to specify any changes or additions to the content. You can also program Soft Keys and specify screen refresh intervals.
The Design Studio User Guide provides detailed information about all transformation rules. The transformations that are specific to IP phones are also documented in Chapter 2 of this IP Phone Solutions Guide.
Rather than using Design Studio to create transformations, you can include CTE XHTML extensions in HTML or XML files to indicate transformations for an IP phone.
Typically, this method of specifying transformation rules is handled by an application developer during the initial implementation of a web application. An application developer includes XHTML extensions to indicate how the application should be transformed.
The Design Studio User Guide provides detailed information about all CTE XHTML extensions. The extensions that are specific to IP phones are summarized in Chapter 3 of this IP Phone Solutions Guide.
Web Applications on IP Phones
Web applications that are designed for desktop browsers will not work on an IP phone unless the applications are written in XML. The CTE converts web applications requested by IP phones to XML that contains Cisco XML objects. In addition, the CTE automatically transforms the data to improve usability on IP phones.
The following list notes how various data types are handled by IP phones and indicates how you can enhance the default handling through Design Studio:
When an IP phone encounters a new data type (such as an image, link, input field, or text), it displays the data type on a new screen. Suppose that a web page contains the following string that includes text, a link, and an image:
Click here to see
An IP phone displays the word "Click" on the first screen, the link "here" on the second screen, the text "to see" on the third screen, and the image on the fourth screen. You can use Design Studio to improve that presentation, perhaps moving the link after the text, modifying the text, and substituting alternate text for the image.
For a card (a screen) that contains the text data type, the CTE handles link breaks, converts special characters, such as "&", to the format required by the IP phone, and adds the Back and Fwd Soft Keys, as needed.
The CTE drops images that are smaller than 20 pixels in both height and width. You can send a small image to an IP phone by putting the Retain Element rule on the img element. The CTE sends images to an IP phone provided that they are in a format supported by the phone.
An IP phone does not display input type="image" elements. If the image is smaller than 20 pixels in both width and height and you want to send the image to the IP phone (independent of the input field), you can use Design Studio to reference the image from an a href element.
For a card that contains a menu data type, the CTE displays links as a numbered list and adds the Back, Fwd, and Select Soft Keys, as needed. The user can use the keypad to select a link by number.
For a card that contains the input fields data type, the CTE adds the instruction "Enter Input:" and the adds the Back, Ok, and << Soft Keys. The CTE also adds a number to links so that the user can select a link by using the keypad. You can use the Group rule to eliminate elements other than the links (a href elements), thus presenting an uninterrupted list of links.
By default, an input element is set to the Cisco XML object InputFlags="A" (ASCII). You can use the Input Type/Label rule in Design Studio to specify an input type, such as telephone number. By limiting the input type, you can reduce the number of keystrokes required for a user to complete the field.
If an input field on a web page has a default entry that a user most likely has to change, use Design Studio to remove the default entry so that the user does not have to backspace through the entry before adding a new one.
IP phones support dialable phone numbers, which can be specified in links or through a Soft Key. Use Design Studio to make a phone number on a web page dialable or to add a Soft Key that dials a particular phone number.
You can define up to three Soft Keys per card in addition to the default Soft Keys. The CTE adds a More Soft Key that is used to display the additional Soft Keys.
IP phones support the Refresh attribute in an HTTP header. You can use the Refresh rule to indicate a refresh interval for one or more cards.
The CTE provides transparent JavaScript emulation, acting as a proxy server for IP phones. The CTE support for JavaScript provides IP phone access to JavaScript-dependent form manipulation, event processing, browser redirection, and cookie handling.
You do not need to make any changes for JavaScript to operate correctly on IP phones. However, you can apply transformation rules to a page that contains JavaScript in order to refine the presentation, as described in "Working with JavaScript" in the Design Studio User Guide.
