An inbound access list has been configured on a serial interface to deny packet entry for TCP and UDP ports 21， 23 and 25. What types of packets will be permitted by this ACL (Choose three.)（）。

组成自适应代理网关防火墙的基本要素有两个:自适应代理服务器 (Adaptive Proxysewer) 与动态包过滤器 (Dynamic Packet Filter) 。

GPRS的英文全称为：（）。 A: AGlobal Packet Radio Service B: BGeneral Packet Radio Service C: CGeneral Packet Radio System D: DGlobal Packet Radio System

What kind of filter is used to extract a single-freq. harmonic from the harmonic components contained in square wave? A: Low-pass Filter B: High-pass Filter C: Band-pass Filter D: Band-elimination Filter

You can see（）on the table. A: a packet of prawn B: two packets of prawn C: a packet of praw

We can employ the next filters to detect edges from an image: A: Roberts filter B: Sobel filter C: mean filter D: Gaussian filter

The filter [img=142x47]18031c9cd67f894.png[/img] is a lowpass filter

下列关于Filter的描述中，正确的是 （）。 A: Filter只能过滤页面 B: Filter只能过滤Servlet C: Filter程序必须实现Filter接口 D: 一个web应用只能注册一个Filte

filter ____

在一个Filter中，处理filter业务的是（）方法