gkalpak · Apr 12, 2018 · Apr 12, 2018 · Apr 12, 2018 · Apr 12, 2018
diff --git a/aio/content/guide/service-worker-config.md b/aio/content/guide/service-worker-config.md
@@ -1,5 +1,3 @@
-{@a glob}
-
 # Service worker configuration
 
 #### Prerequisites
@@ -9,9 +7,9 @@ A basic understanding of the following:
 
 <hr />
 
-The `src/ngsw-config.json` configuration file specifies which files and data URLs the Angular 
-service worker should cache and how it should update the cached files and data. The 
-CLI processes the configuration file during `ng build --prod`. Manually, you can process 
+The `src/ngsw-config.json` configuration file specifies which files and data URLs the Angular
+service worker should cache and how it should update the cached files and data. The
+CLI processes the configuration file during `ng build --prod`. Manually, you can process
 it with the `ngsw-config` tool:
 
 ```sh
@@ -20,10 +18,11 @@ ngsw-config dist src/ngsw-config.json /base/href
 
 The configuration file uses the JSON format. All file paths must begin with `/`, which is the deployment directory&mdash;usually `dist` in CLI projects.
 
-Patterns use a limited glob format:
+{@a glob-patterns}
+Unless otherwise noted, patterns use a limited glob format:
 
 * `**` matches 0 or more path segments.
-* `*` matches exactly one path segment or filename segment.
+* `*` matches 0 or more characters excluding `/`.
 * The `!` prefix marks the pattern as being negative, meaning that only files that don't match the pattern will be included.
 
 Example patterns:
@@ -32,13 +31,14 @@ Example patterns:
 * `/*.html` specifies only HTML files in the root.
 * `!/**/*.map` exclude all sourcemaps.
 
-Each section of the configuration file is described below. 
+Each section of the configuration file is described below.
 
 ## `appData`
 
 This section enables you to pass any data you want that describes this particular version of the app.
 The `SwUpdate` service includes that data in the update notifications. Many apps use this section to provide additional information for the display of UI popups, notifying users of the available update.
 
+{@a index-file}
 ## `index`
 
 Specifies the file that serves as the index page to satisfy navigation requests. Usually this is `/index.html`.
@@ -92,7 +92,7 @@ The `installMode` determines how these resources are initially cached. The `inst
 
 For resources already in the cache, the `updateMode` determines the caching behavior when a new version of the app is discovered. Any resources in the group that have changed since the previous version are updated in accordance with `updateMode`.
 
-* `prefetch` tells the service worker to download and cache the changed resources immediately. 
+* `prefetch` tells the service worker to download and cache the changed resources immediately.
 
 * `lazy` tells the service worker to not cache those resources. Instead, it treats them as unrequested and waits until they're requested again before updating them. An `updateMode` of `lazy` is only valid if the `installMode` is also `lazy`.
 
@@ -104,7 +104,8 @@ This section describes the resources to cache, broken up into three groups.
 
 * `versionedFiles` is like `files` but should be used for build artifacts that already include a hash in the filename, which is used for cache busting. The Angular service worker can optimize some aspects of its operation if it can assume file contents are immutable.
 
-* `urls` includes both URLs and URL patterns that will be matched at runtime. These resources are not fetched directly and do not have content hashes, but they will be cached according to their HTTP headers. This is most useful for CDNs such as the Google Fonts service.
+* `urls` includes both URLs and URL patterns that will be matched at runtime. These resources are not fetched directly and do not have content hashes, but they will be cached according to their HTTP headers. This is most useful for CDNs such as the Google Fonts service.<br>
+  _(Negative glob patterns are not supported.)_
 
 ## `dataGroups`
 
@@ -130,12 +131,13 @@ export interface DataGroup {
 Similar to `assetGroups`, every data group has a `name` which uniquely identifies it.
 
 ### `urls`
-A list of URL patterns. URLs that match these patterns will be cached according to this data group's policy.
+A list of URL patterns. URLs that match these patterns will be cached according to this data group's policy.<br>
+  _(Negative glob patterns are not supported.)_
 
 ### `version`
 Occasionally APIs change formats in a way that is not backward-compatible. A new version of the app may not be compatible with the old API format and thus may not be compatible with existing cached resources from that API.
 
-`version` provides a mechanism to indicate that the resources being cached have been updated in a backwards-incompatible way, and that the old cache entries&mdash;those from previous versions&mdash;should be discarded. 
+`version` provides a mechanism to indicate that the resources being cached have been updated in a backwards-incompatible way, and that the old cache entries&mdash;those from previous versions&mdash;should be discarded.
 
 `version` is an integer field and defaults to `0`.
 
@@ -167,3 +169,38 @@ The Angular service worker can use either of two caching strategies for data res
 
 * `freshness` optimizes for currency of data, preferentially fetching requested data from the network. Only if the network times out, according to `timeout`, does the request fall back to the cache. This is useful for resources that change frequently; for example, account balances.
 
+## `navigationUrls`
+
+This optional section enables you to specify a custom list of URLs that will be redirected to the index file.
+
+### Handling navigation requests
+
+The ServiceWorker will redirect navigation requests that don't match any `asset` or `data` group to the specified [index file](#index-file). A request is considered to be a navigation request if:
+
+1. Its [mode](https://developer.mozilla.org/en-US/docs/Web/API/Request/mode) is `navigation`.
+2. It accepts a `text/html` response (as determined by the value of the `Accept` header).
+3. Its URL matches certain criteria (see below).
+
+By default, these criteria are:
+
+1. The URL must not contain a file extension (i.e. a `.`) in the last path segment.
+2. The URL must not contain `__`.
+
+### Matching navigation request URLs
+
+While these default criteria are fine in most cases, it is sometimes desirable to configure different rules. For example, you may want to ignore specific routes (that are not part of the Angular app) and pass them through to the server.
+
+This field contains an array of URLs and [glob-like](#glob-patterns) URL patterns that will be matched at runtime. It can contain both negative patterns (i.e. patterns starting with `!`) and non-negative patterns and URLs.
+
+Only requests whose URLs match _any_ of the non-negative URLs/patterns and _none_ of the negative ones will be considered navigation requests. The URL query will be ignored when matching.
+
+If the field is omitted, it defaults to:
+
+```ts
+[
+  '/**',           // Include all URLs.
+  '!/**/*.*',      // Exclude URLs to files.
+  '!/**/*__*',     // Exclude URLs containing `__` in the last segment.
+  '!/**/*__*/**',  // Exclude URLs containing `__` in any other segment.
+]
+```