Internet Engineering Task Force (IETF) J. Winterbottom
Request for Comments: 5964 M. Thomson
Category: Standards Track Andrew Corporation
ISSN: 2070-1721 August 2010
Internet Engineering Task Force (IETF) J. Winterbottom
Request for Comments: 5964 M. Thomson
Category: Standards Track Andrew Corporation
ISSN: 2070-1721 August 2010
Specifying Holes in Location-to-Service Translation (LoST) Service Boundaries
指定位置到服务转换（丢失）服务边界中的孔
Abstract
摘要
This document describes how holes can be specified in geodetic service boundaries. One means of implementing a search solution in a service database, such as one might provide with a Location-to-Service Translation (LoST) server, is described.
本文档描述了如何在大地测量服务边界中指定孔。描述了在服务数据库中实现搜索解决方案的一种方法，例如可以提供位置到服务转换（LoST）服务器的方法。
Status of This Memo
关于下段备忘
This is an Internet Standards Track document.
这是一份互联网标准跟踪文件。
This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741.
本文件是互联网工程任务组（IETF）的产品。它代表了IETF社区的共识。它已经接受了公众审查，并已被互联网工程指导小组（IESG）批准出版。有关互联网标准的更多信息，请参见RFC 5741第2节。
Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc5964.
有关本文件当前状态、任何勘误表以及如何提供反馈的信息，请访问http://www.rfc-editor.org/info/rfc5964.
Copyright Notice
版权公告
Copyright (c) 2010 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2010 IETF信托基金和确定为文件作者的人员。版权所有。
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.
本文件受BCP 78和IETF信托有关IETF文件的法律规定的约束(http://trustee.ietf.org/license-info)自本文件出版之日起生效。请仔细阅读这些文件，因为它们描述了您对本文件的权利和限制。从本文件中提取的代码组件必须包括信托法律条款第4.e节中所述的简化BSD许可证文本，并提供简化BSD许可证中所述的无担保。
Table of Contents
目录
1. Introduction ....................................................2
2. Terminology .....................................................3
3. Specifying Holes ................................................3
4. GML Polygons ....................................................6
5. Holes in GML Polygons ...........................................6
6. Service Boundary Specification and Selection Algorithm ..........7
7. Security Considerations ........................................10
8. Acknowledgements ...............................................10
9. References .....................................................10
9.1. Normative References ......................................10
9.2. Informative References ....................................10
1. Introduction ....................................................2
2. Terminology .....................................................3
3. Specifying Holes ................................................3
4. GML Polygons ....................................................6
5. Holes in GML Polygons ...........................................6
6. Service Boundary Specification and Selection Algorithm ..........7
7. Security Considerations ........................................10
8. Acknowledgements ...............................................10
9. References .....................................................10
9.1. Normative References ......................................10
9.2. Informative References ....................................10
The LoST protocol [RFC5222] maps service and locations to destination addresses. A LoST server does this by provisioning boundary maps or areas against service URNs. The boundary is a polygon made up of sets of geodetic coordinates specifying an enclosed area. In some circumstances, an area enclosed by a polygon, also known as an exterior polygon, may contain exception areas, or holes, that for the same service must yield a different destination to that described by the larger area.
丢失协议[RFC5222]将服务和位置映射到目标地址。丢失的服务器通过针对服务URN提供边界映射或区域来实现这一点。边界是由指定封闭区域的大地坐标集组成的多边形。在某些情况下，由多边形（也称为外部多边形）包围的区域可能包含例外区域或孔，对于相同的服务，这些区域必须产生与较大区域所描述的不同的目的地。
This document describes a profile of Geographic Markup Language (GML) [ISO-19107] polygons that constrains their representation when used for describing service boundaries. The profile removes a number of permutations that are difficult to process. This allows for simplified implementations that are not capable of handling all potential variations allowed by GML. A fully conformant GML implementation must produce polygons that fit this profile to ensure interoperability.
本文档描述了地理标记语言（GML）[ISO-19107]多边形的配置文件，当用于描述服务边界时，这些多边形约束其表示。配置文件删除了许多难以处理的排列。这使得简化的实现无法处理GML允许的所有潜在变化。完全一致的GML实现必须生成符合此配置文件的多边形，以确保互操作性。
o--------------o
/ \
/ /\ \
/ + +-----+ \
o | Hole \ o
| | 1 / |
| +-------+ |<--- Primary Polygon
| +-------+ |
| / Hole | |
o \ 2 | o
\ +-----+ + /
\ \/ /
\ /
o--------------o
o--------------o
/ \
/ /\ \
/ + +-----+ \
o | Hole \ o
| | 1 / |
| +-------+ |<--- Primary Polygon
| +-------+ |
| / Hole | |
o \ 2 | o
\ +-----+ + /
\ \/ /
\ /
o--------------o
Figure 1: Holes in a Polygon
图1：多边形中的孔
This document describes a profile of GML [ISO-19107] polygons that constrains their representation when used for describing service boundaries.
本文档描述了GML[ISO-19107]多边形的轮廓，当用于描述服务边界时，该轮廓会限制其表示。
The working group considered that the types of regions described in this memo could be represented in various ways as polygons without holes, but concluded on the recommendations here to avoid potential problems with the arbitrary division of regions and to align with existing geospatial system practices.
工作组认为，本备忘录中描述的区域类型可以以各种方式表示为无孔多边形，但总结了此处的建议，以避免区域任意划分的潜在问题，并与现有地理空间系统做法保持一致。
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].
本文件中的关键词“必须”、“不得”、“必需”、“应”、“不应”、“应”、“不应”、“建议”、“可”和“可选”应按照[RFC2119]中所述进行解释。
Holes related to an exterior boundary polygon MUST adhere to the following rules:
与外部边界多边形相关的孔必须遵守以下规则：
Rule 1: Two holes MUST NOT have more than one point of intersection.
规则1：两个孔的交点不得超过一个。
If two or more holes overlap or share a common boundary, then these represent a single hole. The internal elements (holes) should have common boundaries removed and a single hole created irrespective of whether the excluded area is itself made up of multiple service boundaries.
如果两个或多个孔重叠或共享一个公共边界，则这些孔表示单个孔。内部构件（孔）应移除公共边界，并创建一个孔，无论排除区域本身是否由多个服务边界组成。
o--------------o o--------------o
/ \ / \
/ /\ \ / /\ \
/ + +-----+ \ / + +-----+ \
o | Hole \ o o | \ o
| | 1 \ | | | One \ |
| +-+-------+ | =========> | +-+ Hole + |
| / Hole | | | / | |
o \ 2 | o o \ | o
\ +-----+ + / \ +-----+ + /
\ \/ / \ \/ /
\ / \ /
o--------------o o--------------o
o--------------o o--------------o
/ \ / \
/ /\ \ / /\ \
/ + +-----+ \ / + +-----+ \
o | Hole \ o o | \ o
| | 1 \ | | | One \ |
| +-+-------+ | =========> | +-+ Hole + |
| / Hole | | | / | |
o \ 2 | o o \ | o
\ +-----+ + / \ +-----+ + /
\ \/ / \ \/ /
\ / \ /
o--------------o o--------------o
Incorrect Correct
错对
Figure 2: Hole Specification with Boundary Sharing
图2：共享边界的孔规格
Rule 2: A polygon MUST describe a contiguous region.
规则2：多边形必须描述连续区域。
If a hole overlaps with the outer boundary, or it shares part of a side with the outer boundary, then it has an inlet and it MUST be expressed without the hole.
如果孔与外边界重叠，或与外边界共用一部分边，则该孔具有入口，且必须在无孔的情况下表达。
+------- Inlet
|
v
o---+-----+----o o---o o----o
/ |%%%%%| \ / | | \
/ /%%%%%%| \ / / | \
/ +%%%%%%%| \ / o o \
o |%%%%%%%%\ o o | \ o
| |%%%%%%%%%\ | | | \ |
| +-+%%%%%%%%+ | ========> | o-o o |
| /%%%%%%%%| | | / | |
o \%%%%%%%%| o o \ | o
\ +-----+ + / \ o-----o o /
\ \/ / \ \/ /
\ / \ /
o--------------o o--------------o
+------- Inlet
|
v
o---+-----+----o o---o o----o
/ |%%%%%| \ / | | \
/ /%%%%%%| \ / / | \
/ +%%%%%%%| \ / o o \
o |%%%%%%%%\ o o | \ o
| |%%%%%%%%%\ | | | \ |
| +-+%%%%%%%%+ | ========> | o-o o |
| /%%%%%%%%| | | / | |
o \%%%%%%%%| o o \ | o
\ +-----+ + / \ o-----o o /
\ \/ / \ \/ /
\ / \ /
o--------------o o--------------o
Incorrect Correct
错对
Figure 3: Specification of an Inlet
图3：入口的规格
If a hole touches the outer boundary in two places, the region MUST be expressed as two separate polygons.
如果孔在两个位置接触外边界，则该区域必须表示为两个单独的多边形。
A--q-----------B A-q q----------B
/ | | \ / | | \
/ | | \ / | | \
/ z r-----s \ / P z r-----s P \
H | \ C H o | \ o C
| | One \ | | l | \ l |
| y-x Hole t | ========> | y y-x t y |
| / | | | g / | g |
G \ | D G o \ | o D
\ / v---u / \ n / v---u n /
\ \ / / \ 1 \ / 2 /
\ \ / / \ \ / /
F-----w--------E F-----w w--------E
A--q-----------B A-q q----------B
/ | | \ / | | \
/ | | \ / | | \
/ z r-----s \ / P z r-----s P \
H | \ C H o | \ o C
| | One \ | | l | \ l |
| y-x Hole t | ========> | y y-x t y |
| / | | | g / | g |
G \ | D G o \ | o D
\ / v---u / \ n / v---u n /
\ \ / / \ 1 \ / 2 /
\ \ / / \ \ / /
F-----w--------E F-----w w--------E
Incorrect Correct
错对
Figure 4: Specification of Hole with Multiple Outer-Boundary Intersections
图4：具有多个外边界交点的孔规格
Similarly, a polygon that is enclosed entirely within a hole from another polygon (i.e., an "island") is a separate polygon.
类似地，完全封闭在另一个多边形（即“岛”）的孔内的多边形是一个单独的多边形。
o--------------o
/ \
/ +--------------+ \
/ |%%%%%%%%%%%%%%| \
o |%%o--------o%%| o
| |%/ Island \%| |
| |%\ /%| |
| |%%o--------o%%| |
o |%%%%%%%%%%%%%%| o
\ +--------------+ /
\ /
\ /
o--------------o
o--------------o
/ \
/ +--------------+ \
/ |%%%%%%%%%%%%%%| \
o |%%o--------o%%| o
| |%/ Island \%| |
| |%\ /%| |
| |%%o--------o%%| |
o |%%%%%%%%%%%%%%| o
\ +--------------+ /
\ /
\ /
o--------------o
Figure 5: Hole with Enclosed Polygon (Island)
图5：带有封闭多边形的孔（岛）
Rule 3: A hole MUST be formed from a legal linear ring in accordance with [geoshape], except that points are specified in a clockwise direction.
规则3：根据[geoshape]，孔必须由合法的线性环形成，但顺时针方向指定的点除外。
Holes are specified in a clockwise direction so that the upward normal is opposed to the upward normal of the exterior boundary of the polygon. Note that [geoshape] stipulates that exterior boundaries are specified in counterclockwise order.
孔以顺时针方向指定，以便向上法线与多边形外部边界的向上法线相对。请注意，[geoshape]规定按逆时针顺序指定外部边界。
There is no restriction on the number of points that are used to express the perimeter of either exterior or interior boundaries.
用于表示外部边界或内部边界周长的点的数量没有限制。
The GML encoding of a polygon defines a enclosed exterior boundary, with the first and last points of boundary being the same. Consider the example in Figure 6.
多边形的GML编码定义封闭的外部边界，边界的第一个点和最后一个点相同。考虑图6中的示例。
F--------------E
/ \
/ \
/ \
A D
\ /
\ /
\ /
B--------------C
F--------------E
/ \
/ \
/ \
A D
\ /
\ /
\ /
B--------------C
<gml:Polygon srsName="urn:ogc:def:crs:EPSG::4326">
<gml:exterior>
<gml:LinearRing>
<gml:pos>43.311 -73.422</gml:pos> <!--A-->
<gml:pos>43.111 -73.322</gml:pos> <!--B-->
<gml:pos>43.111 -73.222</gml:pos> <!--C-->
<gml:pos>43.311 -73.122</gml:pos> <!--D-->
<gml:pos>43.411 -73.222</gml:pos> <!--E-->
<gml:pos>43.411 -73.322</gml:pos> <!--F-->
<gml:pos>43.311 -73.422</gml:pos> <!--A-->
</gml:LinearRing>
</gml:exterior>
</gml:Polygon>
<gml:Polygon srsName="urn:ogc:def:crs:EPSG::4326">
<gml:exterior>
<gml:LinearRing>
<gml:pos>43.311 -73.422</gml:pos> <!--A-->
<gml:pos>43.111 -73.322</gml:pos> <!--B-->
<gml:pos>43.111 -73.222</gml:pos> <!--C-->
<gml:pos>43.311 -73.122</gml:pos> <!--D-->
<gml:pos>43.411 -73.222</gml:pos> <!--E-->
<gml:pos>43.411 -73.322</gml:pos> <!--F-->
<gml:pos>43.311 -73.422</gml:pos> <!--A-->
</gml:LinearRing>
</gml:exterior>
</gml:Polygon>
Figure 6: Hexagon and Associated GML
图6：六边形和相关GML
Note that polygon vertices in Figure 6 are expressed using <pos> elements for clarity. The vertices can also be expressed using a <posList> element.
请注意，为了清晰起见，图6中的多边形顶点使用<pos>元素表示。顶点也可以使用<posList>元素表示。
A hole is specified in the polygon by defining an interior boundary. The points defining the internal boundary define the area represented by the hole in the primary (exterior) polygon. The shaded area in Figure 7 is represented by the 4 points of the interior boundary specified by (w,z,y,x).
通过定义内部边界在多边形中指定孔。定义内部边界的点定义由主（外部）多边形中的孔表示的区域。图7中的阴影区域由（w，z，y，x）指定的内边界的4个点表示。
F-------------E
/ \
/ w-------------x \
/ |/////////////| \
A |/////////////| D
\ |/////////////| /
\ z-------------y /
\ /
B-------------C
F-------------E
/ \
/ w-------------x \
/ |/////////////| \
A |/////////////| D
\ |/////////////| /
\ z-------------y /
\ /
B-------------C
<gml:Polygon srsName="urn:ogc:def:crs:EPSG::4326">
<gml:exterior>
<gml:LinearRing>
<gml:pos>43.311 -73.422</gml:pos> <!--A-->
<gml:pos>43.111 -73.322</gml:pos> <!--B-->
<gml:pos>43.111 -73.222</gml:pos> <!--C-->
<gml:pos>43.311 -73.122</gml:pos> <!--D-->
<gml:pos>43.511 -73.222</gml:pos> <!--E-->
<gml:pos>43.511 -73.322</gml:pos> <!--F-->
<gml:pos>43.311 -73.422</gml:pos> <!--A-->
</gml:LinearRing>
</gml:exterior>
<gml:interior>
<gml:LinearRing>
<gml:pos>43.411 -73.322</gml:pos> <!--w-->
<gml:pos>43.411 -73.222</gml:pos> <!--x-->
<gml:pos>43.211 -73.222</gml:pos> <!--y-->
<gml:pos>43.211 -73.322</gml:pos> <!--z-->
<gml:pos>43.411 -73.322</gml:pos> <!--w-->
</gml:LinearRing>
</gml:interior>
</gml:Polygon>
<gml:Polygon srsName="urn:ogc:def:crs:EPSG::4326">
<gml:exterior>
<gml:LinearRing>
<gml:pos>43.311 -73.422</gml:pos> <!--A-->
<gml:pos>43.111 -73.322</gml:pos> <!--B-->
<gml:pos>43.111 -73.222</gml:pos> <!--C-->
<gml:pos>43.311 -73.122</gml:pos> <!--D-->
<gml:pos>43.511 -73.222</gml:pos> <!--E-->
<gml:pos>43.511 -73.322</gml:pos> <!--F-->
<gml:pos>43.311 -73.422</gml:pos> <!--A-->
</gml:LinearRing>
</gml:exterior>
<gml:interior>
<gml:LinearRing>
<gml:pos>43.411 -73.322</gml:pos> <!--w-->
<gml:pos>43.411 -73.222</gml:pos> <!--x-->
<gml:pos>43.211 -73.222</gml:pos> <!--y-->
<gml:pos>43.211 -73.322</gml:pos> <!--z-->
<gml:pos>43.411 -73.322</gml:pos> <!--w-->
</gml:LinearRing>
</gml:interior>
</gml:Polygon>
Figure 7: Hexagon with Hole
图7：带孔六边形
A service boundary is represented by a polygon that may have many vertices. The enclosed area of the polygon represents the area in which a service, expressed as a service URN, maps to a single URI.
服务边界由可能具有多个顶点的多边形表示。多边形的封闭区域表示服务（表示为服务URN）映射到单个URI的区域。
Figure 7 is used to illustrate two service boundaries. The first service boundary A->F shall be referred to as area-A, and the second service boundary w->z shall be referred to as area-w. Furthermore, area-A is directly represented by the GML encoding provided in Figure 7. Area-w is represented as a hole in area-A by the interior
图7用于说明两个服务边界。第一个服务边界A->F应称为区域-A，第二个服务边界w->z应称为区域-w。此外，图7中提供的GML编码直接表示区域A。区域-w由内部表示为区域-a中的孔
boundary. Since area-w is also a service boundary, a separate polygon describing this area is also required and is shown in Figure 8 (note the reversal of the vertices).
边界由于w区也是服务边界，因此还需要一个单独的多边形来描述该区域，如图8所示（注意顶点的反转）。
<gml:Polygon srsName="urn:ogc:def:crs:EPSG::4326">
<gml:exterior>
<gml:LinearRing>
<gml:pos>43.411 -73.322</gml:pos> <!--w-->
<gml:pos>43.211 -73.322</gml:pos> <!--z-->
<gml:pos>43.211 -73.222</gml:pos> <!--y-->
<gml:pos>43.411 -73.222</gml:pos> <!--x-->
<gml:pos>43.411 -73.322</gml:pos> <!--w-->
</gml:LinearRing>
</gml:exterior>
</gml:Polygon>
<gml:Polygon srsName="urn:ogc:def:crs:EPSG::4326">
<gml:exterior>
<gml:LinearRing>
<gml:pos>43.411 -73.322</gml:pos> <!--w-->
<gml:pos>43.211 -73.322</gml:pos> <!--z-->
<gml:pos>43.211 -73.222</gml:pos> <!--y-->
<gml:pos>43.411 -73.222</gml:pos> <!--x-->
<gml:pos>43.411 -73.322</gml:pos> <!--w-->
</gml:LinearRing>
</gml:exterior>
</gml:Polygon>
Figure 8: GML for Area-w
图8:w区的GML
Service mappings for these boundaries might be provided by a LoST server in the form shown in Figure 9.
这些边界的服务映射可能由丢失的服务器以图9所示的形式提供。
<mapping xmlns="urn:ietf:params:xml:ns:lost1"
expires="2010-12-25T09:44:33Z"
lastUpdated="2010-03-08T03:48:22Z"
source="authoritative.foo.example"
sourceId="7e3f40b098c711dbb606011111111111">
<displayName xml:lang="en">Outer Area Police</displayName>
<service>urn:service:sos.police</service>
<serviceBoundary profile="geodetic-2d">
<gml:Polygon xmlns:gml="http://www.opengis.net/gml"
srsName="urn:ogc:def:crs:EPSG::4326">
<gml:exterior>
<gml:LinearRing>
<gml:pos>43.311 -73.422</gml:pos>
<gml:pos>43.111 -73.322</gml:pos>
<gml:pos>43.111 -73.222</gml:pos>
<gml:pos>43.311 -73.122</gml:pos>
<gml:pos>43.511 -73.222</gml:pos>
<gml:pos>43.511 -73.322</gml:pos>
<gml:pos>43.311 -73.422</gml:pos>
</gml:LinearRing>
</gml:exterior>
<!-- this is the service boundary hole -->
<gml:interior>
<gml:LinearRing>
<gml:pos>43.411 -73.322</gml:pos>
<gml:pos>43.211 -73.322</gml:pos>
<gml:pos>43.211 -73.222</gml:pos>
<mapping xmlns="urn:ietf:params:xml:ns:lost1"
expires="2010-12-25T09:44:33Z"
lastUpdated="2010-03-08T03:48:22Z"
source="authoritative.foo.example"
sourceId="7e3f40b098c711dbb606011111111111">
<displayName xml:lang="en">Outer Area Police</displayName>
<service>urn:service:sos.police</service>
<serviceBoundary profile="geodetic-2d">
<gml:Polygon xmlns:gml="http://www.opengis.net/gml"
srsName="urn:ogc:def:crs:EPSG::4326">
<gml:exterior>
<gml:LinearRing>
<gml:pos>43.311 -73.422</gml:pos>
<gml:pos>43.111 -73.322</gml:pos>
<gml:pos>43.111 -73.222</gml:pos>
<gml:pos>43.311 -73.122</gml:pos>
<gml:pos>43.511 -73.222</gml:pos>
<gml:pos>43.511 -73.322</gml:pos>
<gml:pos>43.311 -73.422</gml:pos>
</gml:LinearRing>
</gml:exterior>
<!-- this is the service boundary hole -->
<gml:interior>
<gml:LinearRing>
<gml:pos>43.411 -73.322</gml:pos>
<gml:pos>43.211 -73.322</gml:pos>
<gml:pos>43.211 -73.222</gml:pos>
<gml:pos>43.411 -73.222</gml:pos>
<gml:pos>43.411 -73.322</gml:pos>
</gml:LinearRing>
</gml:interior>
</gml:Polygon>
</serviceBoundary>
<uri>sip:area-A-pd@example.com</uri>
<uri>xmpp:area-A-pd@example.com</uri>
<serviceNumber>000</serviceNumber>
</mapping>
<gml:pos>43.411 -73.222</gml:pos>
<gml:pos>43.411 -73.322</gml:pos>
</gml:LinearRing>
</gml:interior>
</gml:Polygon>
</serviceBoundary>
<uri>sip:area-A-pd@example.com</uri>
<uri>xmpp:area-A-pd@example.com</uri>
<serviceNumber>000</serviceNumber>
</mapping>
<mapping xmlns="urn:ietf:params:xml:ns:lost1"
expires="2010-12-25T09:44:33Z"
lastUpdated="2010-03-08T03:48:22Z"
source="authoritative.foo.example"
sourceId="7e3f40b098c711dbb606011111111111">
<displayName xml:lang="en">Inner Area Police</displayName>
<service>urn:service:sos.police</service>
<serviceBoundary profile="geodetic-2d">
<gml:Polygon xmlns:gml="http://www.opengis.net/gml"
srsName="urn:ogc:def:crs:EPSG::4326">
<gml:exterior>
<gml:LinearRing>
<gml:pos>43.411 -73.322</gml:pos>
<gml:pos>43.211 -73.322</gml:pos>
<gml:pos>43.211 -73.222</gml:pos>
<gml:pos>43.411 -73.222</gml:pos>
<gml:pos>43.411 -73.322</gml:pos>
</gml:LinearRing>
</gml:exterior>
</gml:Polygon>
</serviceBoundary>
<uri>sip:area-w-pd@example.com</uri>
<uri>xmpp:area-w-pd@example.com</uri>
<serviceNumber>000</serviceNumber>
</mapping>
<mapping xmlns="urn:ietf:params:xml:ns:lost1"
expires="2010-12-25T09:44:33Z"
lastUpdated="2010-03-08T03:48:22Z"
source="authoritative.foo.example"
sourceId="7e3f40b098c711dbb606011111111111">
<displayName xml:lang="en">Inner Area Police</displayName>
<service>urn:service:sos.police</service>
<serviceBoundary profile="geodetic-2d">
<gml:Polygon xmlns:gml="http://www.opengis.net/gml"
srsName="urn:ogc:def:crs:EPSG::4326">
<gml:exterior>
<gml:LinearRing>
<gml:pos>43.411 -73.322</gml:pos>
<gml:pos>43.211 -73.322</gml:pos>
<gml:pos>43.211 -73.222</gml:pos>
<gml:pos>43.411 -73.222</gml:pos>
<gml:pos>43.411 -73.322</gml:pos>
</gml:LinearRing>
</gml:exterior>
</gml:Polygon>
</serviceBoundary>
<uri>sip:area-w-pd@example.com</uri>
<uri>xmpp:area-w-pd@example.com</uri>
<serviceNumber>000</serviceNumber>
</mapping>
Figure 9: Service Boundary Specifications
图9：服务边界规范
It is considered likely that LoST servers will need to provide responses sufficiently quickly to allow real-time queries to be performed as part of an emergency call routing flow. It is for this reason that databases supporting native geospatial query techniques are desirable and that service boundary specifications that are easily mapped to internal data structures are preferred. Using interior boundaries makes support for this operation easy, while allowing an arbitrary number of holes in a service boundary to be specified.
据认为，丢失的服务器可能需要提供足够快的响应，以便作为紧急呼叫路由流程的一部分执行实时查询。正是由于这个原因，支持本地地理空间查询技术的数据库是可取的，并且容易映射到内部数据结构的服务边界规范是首选的。使用内部边界可以轻松支持此操作，同时允许在服务边界中指定任意数量的孔。
Each polygon is stored in the geospatial database and mapped to a service URN and destination URI. Many geospatial databases natively support polygons with interior exclusions. Without native support, interior boundaries can be stored against the polygon and can checked separately. A location falls within the area described by a polygon if it is within the exterior boundary and not within any interior boundary.
每个多边形存储在地理空间数据库中，并映射到服务URN和目标URI。许多地理空间数据库本机支持带有内部排除的多边形。如果没有本机支持，内部边界可以存储在多边形上，并且可以单独检查。如果某个位置位于外部边界内而不在任何内部边界内，则该位置位于多边形所描述的区域内。
In the above example, if a location falls within the interior boundary, it maps to the "Inner Area Police" service; likewise, if a location falls within the exterior boundary, but not within the interior boundary, it maps to the "Outer Area Police" service.
在上面的示例中，如果某个位置位于内部边界内，它将映射到“内部区域警察”服务；同样，如果某个位置位于外部边界内，但不在内部边界内，则该位置将映射到“外部区域警察”服务。
Constraining the form of a polygon representation as described in this document does not introduce new security considerations.
约束本文档中描述的多边形表示形式不会引入新的安全注意事项。
Thanks to Carl Reed for input provided to the list some months back and for reviewing this document. Thanks to Michael Haberler for suggesting that such a specification is required. Thanks to Avery Penniston for review and feedback.
感谢Carl Reed几个月前为列表提供的信息以及对本文件的审阅。感谢Michael Haberler建议需要这样的规范。感谢Avery Penniston的审查和反馈。
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2119]Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，1997年3月。
[RFC5222] Hardie, T., Newton, A., Schulzrinne, H., and H. Tschofenig, "LoST: A Location-to-Service Translation Protocol", RFC 5222, August 2008.
[RFC5222]Hardie，T.，Newton，A.，Schulzrinne，H.，和H.Tschofenig，“丢失：位置到服务转换协议”，RFC 5222，2008年8月。
[geoshape] Thomson, M. and C. Reed, "GML 3.1.1 PIDF-LO Shape Application Schema for use by the Internet Engineering Task Force (IETF)", Candidate OpenGIS Implementation Specification 06-142r1, Version: 1.0, April 2007.
[geoshape]Thomson，M.和C.Reed，“互联网工程任务组（IETF）使用的GML 3.1.1 PIDF-LO形状应用模式”，候选OpenGIS实施规范06-142r1，版本：1.0，2007年4月。
[ISO-19107] ISO, "Geographic information - Spatial Schema", ISO Standard 19107, First Edition, May 2003.
[ISO-19107]ISO，“地理信息-空间模式”，ISO标准19107，第一版，2003年5月。
Authors' Addresses
作者地址
James Winterbottom Andrew Corporation Andrew Building (39) Wollongong University Campus Northfields Avenue Wollongong, NSW 2522 AU
James Winterbottom Andrew Corporation Andrew Building（39）卧龙岗大学校园北田大道，新南威尔士州卧龙岗2522 AU
EMail: james.winterbottom@andrew.com
EMail: james.winterbottom@andrew.com
Martin Thomson Andrew Corporation Andrew Building (39) Wollongong University Campus Northfields Avenue Wollongong, NSW 2522 AU
马丁·汤姆森·安德鲁公司安德鲁大厦（39）卧龙岗大学校园北田大道卧龙岗，新南威尔士州2522
EMail: martin.thomson@andrew.com
EMail: martin.thomson@andrew.com