Understanding how Content Analyzer sets main and alternate routes in the map is critical to your site management work. In fact, you can decide how to set routes in your map, and whether to display alternate routes at all. You can also set routes one way when you first create a map, then change them later. This chapter takes a closer look at main and alternate routes and some of the things you can do with them:
Taking a Shortcut to the Main Route
Changing How Alternate Routes are Displayed in the Tree View
Allowing or Disabling Expansion of Alternate Routes
When you're surfing the Web, there are often many hyperlinks throughout the site that allow you to jump to the same page. Our term for these multiple jumping-off places is alternate routes, and they're displayed in green in the map.
You can set routes in a WebMap in various ways, as described in "Different Ways to Set Routes." To reset the routes, see "Resetting the Routes."
Later, after you've created the map, you can set routes according to usage data you've imported (if you have imported usage data) or by URL hierarchy (using the Mapping|Set Routes command).
The topics that follow describe the various ways routes can be set in a WebMap.
For example, if your site is at www.mysite.com, the map hierarchy is built according to the way URLs are linked off this domain. The first-level, main-route children of www.mysite.com are only those subdirectories immediately off the site root. If there are any links on the site's home page that point to a place deeper in the site--for instance, www.mysite.com/products/widget--they appear in the map as main-route children of the /products area of the site (and as alternate routes off the site's home page).
Suppose that one level down in your site, there are branches at www.mysite.com/products and www.mysite.com/corporate. When Content Analyzer builds the map according to the URL hierarchy, it first maps the home page, www.mysite.com/index.html. It then maps any objects that are also at the site root level of the site.
Once those objects are mapped, Content Analyzer moves on to the /products and /corporate branches, mapping all objects in those branches as first-level children of the home page. It then maps objects at the next level down from /products and /corporate--that is, the grandchildren of the home page. It continues exploring objects in this way until the entire map is built.
Note: If there's a "tie" for a parent in the directory hierarchy, a default page (index.htm, default.htm, welcome.htm) always wins. Also, a non-default page can never be the parent of a default page in the same directory.
If there are any links in one area of the site to objects in another area--say, from the /products branch to the /corporate branch, those links appear as main-route children of the /corporate branch, not the page that contains the link (they are alternate routes off that page). For example, say /products/widgets.html contains a link to a page whose URL is /corporate/execstaff.html. Assume also that /corporate/index.html contains a link to execstaff.html. The execstaff page will be a main-route child of www.mysite.com/corporate, and an alternate-route child of www.mysite.com/products.
Note that if you're using any aliases in your URLs, the URL hierarchy is not necessarily the same as your site's directory hierarchy on disk. For instance, you may have a CGI Bin directory that is actually on disk at www.mysite.com/cgi/myscripts. But if the URL to this directory is aliased as www.mysite.com/cgi-bin, Content Analyzer considers any files in /cgi/myscripts to be located at www.mysite.com/cgi-bin--that is, children of the home page, not children of /cgi.
Contrast this route-setting method to the breadth-first method described in "Setting Routes Breadth-first (Shortest Main Route)."
Content Analyzer first looks up all links on the home page, then the hyperlinks on those pages, and so on, working down through the site one level at a time. It makes no decisions about whether a particular link might be more important (or "main") as a child of a different page. For instance, home pages often contain links that point to many different areas of the site. There might be a link to a page buried deep in the site. Yet when you look at the WebMap, that link is shown as a first-level child of the home page, very high in the site structure.
Using the example from the previous section, if Content Analyzer first encounters a link to www.mysite.com/corporate/execstaff.html on www.mysite.com/products/index.html, the execstaff page is shown as a main-route child of /products/index.html. If Content Analyzer then encounters a link to execstaff on www/microsoft.com/corporate/index.html--that is, on its parent page in the hierarchy--execstaff is shown as an alternate-route child.
You'll want to let Content Analyzer set routes breadth-first if you are most interested in seeing objects mapped as they're discovered, regardless of where they are in the site hierarchy.
Warning: You can only set routes breadth-first when you first create a map. If you've already built the map and set routes by URL hierarchy, you can't change the existing map's structure to breadth-first; you have to build the map again from scratch.
Note that this option is relevant only if you've imported usage data into your map; see "Importing Usage Data" in Chapter 8, "Site Management Tips & Techniques," for details. Note also that the busiest links between objects in your site are shown with magenta lines in the Cyberbolic view.
Continuing the example of the previous two sections, suppose there is a page with the URL www.mysite.com/products/whizbang.html. There are three pages that point to whizbang: the site's home page (index.html), /corporate/newstuff.html, and /products/productline.html. Of these three InLinks, the link on the home page has received the most hits. When you set routes by usage data, Content Analyzer makes whizbang a main-route child of the home page, even though whizbang's actual position in the URL hierarchy is further down in the site (under /products).
To do so, right-click an alternate route (shown in green) that you think should be a main route and then choose Make Main Route from the right-click menu. This swaps the main route and alternate route for that object.
On the other hand, when you show alternate routes with object icons, you get a better look at which resources are available in your site. (You can still tell which objects are alternate routes because they are green. See "Object and Route Label Colors" in Chapter 2, "Anatomy of a WebMap.") For instance, if there is more than one hyperlink to a particular image, you can see at a glance what pages contain those hyperlinks, and thus get an idea of why the image is referred to so often.
Note that only alternate routes can be displayed with link icons. Main-route objects are always depicted with their object icons. For instance, the main route to an image will always show the Mona Lisa icon.
The alternate route icons use arrows to show the hierarchical relationship between the page where the link originates and the object the link points to. The following map shows several of the link icons you might see.
Link icons give you information about the site's structure
You might notice that many of the "up-links" point back to the site's home page or back to a topic introduction page (instead of to different information in the site). These types of links are purely navigational. If you're publishing the map, and you're going to include alternate routes in the published version, you might want to hide up-links to the home page; otherwise, your published map might be too cluttered.
You can select a page in the map and use the Link Info window (View|Object Links) to see the alternate links originating on that page. They're shown in green, just like in the map.
Links on the selected page, with alternate routes shown in green
On the other hand, you may want to allow expansion of alternate routes if you like to use the map in much the same way as you browse: following hyperlinks around the site as the mood strikes you, even if those links are buried deep within the site.
In this map, alternate routes are expandable
Main-route link icons under an expanded alternate route
