Access Control 接入控制

当有大量的UE请求接入同一个基站时，各个UE的信号可能会互相干扰，导致无法被基站解码（视为噪音）；即使有幸接入被解码但也会造成基站自身负载过大。在这种情况下，基站会限制请求接入的UE的数量，即接入控制Access Control。

限制方法：
1. 接受UE的初始化接入但网络发送拒绝消息（RRC Connection Reject/Attach Rreject）；
2. 阻止UE自身尝试初始化接入（即barring）
Type1：阻止UE任何类型的接入，甚至是紧急呼叫（由SIB1进行配置cellBarred notBarred,）
Type2：阻止特定的UE（USIM中有特定标志EF ACC）获得特定的服务（由SIB2进行配置）

EF ACC存储access class，取值0-9（HPLMN+VPLMN）,11-15（11,15 specified for HPLMN，12,13,14 specified for HPLMN MCC）
class 0~9   普通用户
class 11   PLMN管理
class 12   安全部门使用
class 13   公用事业部门（水、煤气等）
class 14   紧急业务
class 15   PLMN职员

UE侧：EF ACC
ACC(access control class)：随机分配一个normal class（必选，0~9）+ 特定分配specific class（可选,11~15）

网络侧：
网络侧的配置C0~C15由网络操作员设置，一般默认值均为1。在基站安装、维护、测试过程中可将某些比特位如C0~C9设置为0，强行禁止普通用户的接入，从而减少对维护的影响。

http://www.sharetechnote.com/

Access Control by SIB1 : Cell Barring

Access Control by SIB2 : ac-Barring

You may easily guess the Access Control Mechanism by SIB2. You would see several different copies of the following structure. Just by looking at the name of the parameters, you may guess 'this is to allowing (or barring) a certain UE group (Access Class) to a certain service with only a certain probability'.

ac-BarringForXXXXXX

ac-BarringFactor: pXY (0)

ac-BarringTime: sA (0)

ac-BarringForSpecialAC: ABCDE (bitmap)

XXXXX here represents the name of the service (application).
ac-BarringFactor represents the probability of allowance of the access.
ac-BarringForSpecialAC represents Access Class for UEs. A = 11, B = 12, C = 13, D = 14, E = 15

For example,

Let's assume that pXY is set to be p50 and ac-BarringForSpecialAC is set to be 01000. This bitmap indicates the status of each Access Class as follows.

AC 11 = Not Barring
   AC 12 = Barring
   AC 13 = Not Barring
   AC 14 = Not Barring
   AC 15 = Not Barring

Therefore, this barring applies only to the UE that has Access Class 12 is set to be '1' in its USIM.

With this SIB settings, If a UE belonging to Access Class 12 sees this SIB parameter, it generate a random number between 0 and 1. If the number is lower than 0.5 (p50), it is allowed to get access. If the number is higher than 0.5, it should not get access. UE can retry this with the everage interval of A seconds set in ac-BarringTime when it is necessary.

ssac：Service Specific Access Control

Access Control 接入控制相关推荐

[认证授权] 6.Permission Based Access Control
在前面5篇博客中介绍了OAuth2和OIDC(OpenId Connect),其作用是授权和认证.那么当我们得到OAuth2的Access Token或者OIDC的Id Token之后,我们的资源服务 ...
ORA-24247: network access denied by access control list (ACL)
Using UTL_SMTP to send email from your oracle database has changed in Oracle 11g. Or – to be more pr ...
J0ker的CISSP之路:复习Access Control(10)
本文同时发布在:[url]http://netsecurity.51cto.com/art/200806/77992.htm[/url] 在<J0ker的CISSP之路>的上一篇文章< ...
Phalcon 訪问控制列表 ACL（Access Control Lists ACL）
Phalcon在权限方面通过 Phalcon\Acl 提供了一个轻量级的 ACL(訪问控制列表). Access Control Lists (ACL) 同意系统对用户的訪问权限进行控制,比方同意訪问 ...
CISCO SECURE ACCESS CONTROL SERVER
CISCO SECURE ACCESS CONTROL SERVER 安全访问控制服务器为思科智能信息网络提供基于身份的全面的访问控制解决方案.它是用于管理企业网络用户.管理员和网络基础设施资源的集成 ...
【原创】RabbitMQ 之 Access Control（翻译）
2019独角兽企业重金招聘Python工程师标准>>> Access Control When the server first starts running, and detect ...
关于跨域 Response to preflight request doesn‘t pass access control check
做项目的时候由于访问了不同的服务器,然后导致了跨域问题,报错情况为: has been blocked by CORS policy: Response to preflight request do ...
Apache ZooKeeper - ZK的ACL权限控制( Access Control List )
文章目录概述权限模式(Scheme) 口令验证范围验证 Super权限模式授权对象(ID) 权限信息(Permission) ACL相关命令跳过ACL检测实操ACL 生成授权ID 方式一 ...
体验Windows Azure的Access Control Service
我在工作之余写了个和工作内容相关的一个网站,ASP MVC2 + Azure Storage,并且已经部署到了云端.之后有空就修修补补,坚持了一段时间. 然后有了想要给网站加社交功能的想法了,作出的东 ...

Access Control 接入控制

Access Control 接入控制相关推荐

最新文章

热门文章