openbox lab report initialized
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openbox/openbox_1.txt
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openbox/openbox_1.txt
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#set page(header: [
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#set par(spacing: 6pt)
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#align(center)[#text(size: 11pt)[《网络工程》实验报告]]
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#v(-0.3em)
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#line(length: 100%, stroke: (thickness: 1pt))
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],)
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#show heading: it => box(width: 100%)[
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#v(0.50em)
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#set text(font: hei)
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#it.body
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]
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#outline(title: "目录",depth: 3, indent: 1em)
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#pagebreak()
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#outline(
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title: [图目录],
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target: figure.where(kind: image),
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)
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#show heading: it => box(width: 100%)[
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#v(0.50em)
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#set text(font: hei)
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#counter(heading).display()
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// #h(0.5em)
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#it.body
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]
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#set enum(indent: 0.5em,body-indent: 0.5em,)
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#pagebreak()
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= 实验概述
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== 实验内容
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#para[
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本次实验中有三个小实验：
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+ 基于Openbox-S4测试SDN交换功能
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+ 基于SDN 交换机源码处理openflow协议消息
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+ 实验三 使用 REST API 接口查询交换机的相关功能数据
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本实验报告重点分析第二个小实验的实现细节。
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]
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== 实验要求
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#para[
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1. 熟悉Openbox-S4的基本功能
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2. 熟悉OpenFlow协议的基本消息格式
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3. 熟悉OpenFlow协议的基本消息处理流程
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4. 熟悉REST API接口的基本使用
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]
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// Display inline code in a small box
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// that retains the correct baseline.
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#show raw.where(block: false): it => box(
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text(font: ("Consolas","FangSong_GB2312"), it),
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fill: luma(240),
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inset: (x: 3pt, y: 0pt),
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outset: (y: 3pt),
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radius: 2pt,
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)
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// Display block code in a larger block
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// with more padding.
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#show raw.where(block: true): it => block(
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text(font: ("Consolas","FangSong_GB2312"), it),
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fill: luma(240),
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inset: 10pt,
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radius: 4pt,
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width: 100%,
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)
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= 编写SDN交换机源码处理OpenFlow协议消息
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#para[
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本次实验在`main_user_openflow.c`文件中实现了OpenFlow协议处理逻辑。代码通过多个函数处理不同类型的OpenFlow消息，包括Hello消息、Features Request消息、Flow Stats Request消息等。每个函数都根据消息类型生成相应的回复消息，并通过`send_openflow_message`函数发送给控制器。以下将逐一分析每个函数的实现细节。
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]
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== 本次实验所编写的协议
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#para[
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本次实验实现了OpenFlow协议中的大部分消息处理功能。实验代码涵盖了从交换机特性查询到流表统计、端口统计等多种消息类型的处理。以下是实验编写协议的总结。
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]
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=== 实现的协议
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#para[
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- OFPT_FEATURES_REQUEST：用于获取交换机支持的流表数量、缓冲区大小等特性信息。对应的处理函数为`handle_opfmsg_features_request`。
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- OFPT_GET_CONFIG_REQUEST：用于查询交换机的配置信息，如Miss Send Length等。对应的处理函数为`handle_ofpmsg_get_config_request`。
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- OFPT_MULTIPART_REQUEST：用于处理多种统计信息请求，包括交换机描述信息、流表信息、端口统计信息等。对应的处理函数包括：
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- `handle_ofpmsg_desc`
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- `handle_ofpmsg_flow_stats`
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- `handle_ofpmsg_aggregate`
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- `handle_ofpmsg_table`
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- `handle_ofpmsg_port_stats`
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- `handle_ofpmsg_group_features`
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- `handle_ofpmsg_port_desc`
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- OFPT_PACKET_OUT：用于处理控制器发送的数据包，并根据动作指示将数据包从指定端口发送出去。对应的处理函数为`handle_ofpmsg_packet_out`。
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- OFPT_ROLE_REQUEST：用于配置交换机的角色（如主控制器、从控制器等）。对应的处理函数为`handle__opfmsg_role_request`。
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]
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=== 组内分工
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#para[
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本次实验由组内成员共同完成，每个成员负责不同的消息处理函数。以下是每个成员负责的函数列表。
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#align(center)[#table(
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columns: (55pt, auto),
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rows: 15pt,
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inset: 3pt,
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align: horizon+center,
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table.header(
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[分工], [函数]
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),
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table.cell(rowspan: 7)[王李烜],
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"handle_opfmsg_features_request",
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"handle_ofpmsg_desc",
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"handle_ofpmsg_flow_stats",
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"handle_ofpmsg_aggregate",
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"handle_ofpmsg_table",
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"handle_ofpmsg_port_desc",
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"handle_opfmsg_role_request",
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table.cell(rowspan: 2)[廖中煜],
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"handle_ofpmsg_get_config_request",
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"handle_ofpmsg_packet_out",
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table.cell(rowspan: 2)[王誉潞],
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"handle_ofpmsg_port_stats",
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"handle_ofpmsg_group_features",
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)]
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]
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== 相关数据结构
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#para[
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在`main_user_openflow.c`中，定义了一些关键的数据结构和全局变量，用于处理OpenFlow协议的消息。主要的数据结构包括`ofp_header`、`ofp_switch_features`、`ofp_flow_stats`和`ofp_port_stats`等。这些数据结构用于处理OpenFlow协议中的不同消息类型，如交换机特性请求、流表统计请求、端口统计请求等。
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]
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#para[
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`ofp_header`结构体用于表示OpenFlow消息头，包含协议版本、消息类型、消息长度和事务ID等字段。`ofp_switch_features`结构体用于表示交换机的特性信息，如数据路径ID、缓冲区数量、流表数量等。`ofp_flow_stats`结构体用于表示流表统计信息，如流表项长度、优先级、数据包计数等。`ofp_port_stats`结构体用于表示端口统计信息，如端口号、接收数据包数、发送数据包数等。
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]
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== 消息头构建
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#para[
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在OpenFlow协议中，每个消息都有一个消息头，用于标识消息的版本、类型、长度和事务ID。代码中实现了`build_opfmsg_header`函数，用于构建OpenFlow消息头。该函数接收消息长度、消息类型和事务ID作为参数，并填充消息头的各个字段。通过调用该函数，可以确保消息能够被正确解析和处理。
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]
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== 消息处理函数
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#para[
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代码中实现了多个OpenFlow消息处理函数，每个函数对应一种OpenFlow消息类型。以下是每个函数的详细分析。
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]
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=== 处理Hello消息
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#para[
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`handle_opfmsg_hello`函数用于处理控制器发送的Hello消息。Hello消息是OpenFlow协议中的基础消息，用于交换控制器和交换机之间的协议版本信息。函数首先检查消息头中的`version`字段，判断协议版本是否为1.3。如果版本匹配，则打印接收到的Hello消息；否则，生成一个错误消息并发送给控制器。函数返回`HANDLE`表示消息已处理。
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```c
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static enum ofperr handle_opfmsg_hello(struct ofp_buffer *ofpbuf) {
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if (ofpbuf->header.version == 0x04) {
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printf("RECV HELLO!\n\n\n");
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} else {
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struct ofp_buffer *ofpbuf_reply = (struct ofp_buffer *)build_reply_ofpbuf(OFPT_ERROR, ofpbuf->header.xid, sizeof(struct ofp_header));
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send_openflow_message(ofpbuf_reply, sizeof(struct ofp_header));
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}
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return HANDLE;
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}
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```
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]
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=== 处理Features Request消息
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#para[
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`handle_opfmsg_features_request`函数用于处理控制器发送的Features Request消息。该消息用于查询交换机的特性信息，如支持的流表数量、缓冲区大小等。函数生成一个Features Reply消息，并填充交换机的特性信息，如数据路径ID、缓冲区数量、流表数量等。通过`send_openflow_message`函数将回复消息发送给控制器，并返回`HANDLE`表示消息已处理。
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```c
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static enum ofperr handle_opfmsg_features_request(struct ofp_buffer *ofpbuf) {
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int feature_reply_len = sizeof(struct ofp_switch_features) + sizeof(struct ofp_header);
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struct ofp_buffer *ofpbuf_reply = (struct ofp_buffer *)build_opfmsg_reply_ofpbuf(OFPT_FEATURES_REPLY, ofpbuf->header.xid, feature_reply_len);
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struct ofp_switch_features *feature_reply_msg = (struct ofp_switch_features *)ofpbuf_reply->data;
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feature_reply_msg->datapath_id = 0x0100000000000000;
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feature_reply_msg->n_buffers = htonl(46);
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feature_reply_msg->n_tables = 3;
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feature_reply_msg->capabilities = 0x7;
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send_openflow_message(ofpbuf_reply, feature_reply_len);
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return HANDLE;
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}
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```
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]
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=== 处理Get Config Request消息
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#para[
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`handle_ofpmsg_get_config_request`函数用于处理控制器发送的Get Config Request消息。该消息用于查询交换机的配置信息，如Miss Send Length等。函数生成一个Get Config Reply消息，并填充交换机的配置信息。通过`send_openflow_message`函数将回复消息发送给控制器，并返回`HANDLE`表示消息已处理。
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```c
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static enum ofperr handle_ofpmsg_get_config_request(struct ofp_buffer *ofpbuf) {
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int reply_len = sizeof(struct ofp_switch_config) + sizeof(struct ofp_header);
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struct ofp_buffer *ofpbuf_reply = (struct ofp_buffer *)build_reply_ofpbuf(OFPT_GET_CONFIG_REPLY, ofpbuf->header.xid, reply_len);
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struct ofp_switch_config *switch_config_reply = (struct ofp_switch_config *)ofpbuf_reply->data;
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switch_config_reply->flags = htons(0x0000);
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switch_config_reply->miss_send_len = htons(32);
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send_openflow_message(ofpbuf_reply, reply_len);
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return HANDLE;
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}
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```
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]
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=== 处理Description Request消息
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#para[
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`handle_ofpmsg_desc`函数用于处理控制器发送的Description Request消息。该消息用于查询交换机的描述信息，如制造商、硬件版本等。函数生成一个Multipart Reply消息，并填充交换机的描述信息。通过`send_openflow_message`函数将回复消息发送给控制器，并返回`HANDLE`表示消息已处理。
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```c
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static enum ofperr handle_ofpmsg_desc(struct ofp_buffer *ofpbuf) {
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int reply_len = sizeof(struct ofp_header) + sizeof(struct ofp_multipart) + sizeof(struct ofp_desc_stats);
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struct ofp_buffer *ofpbuf_reply = (struct ofp_buffer *)build_reply_ofpbuf(OFPT_MULTIPART_REPLY, ofpbuf->header.xid, reply_len);
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struct ofp_multipart *ofpmp_reply = (struct ofp_multipart *)ofpbuf_reply->data;
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static const char *default_mfr_desc = "Wanglixuan";
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static const char *default_hw_desc = "Lixuan_OpenBox";
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static const char *default_sw_desc = "Lixuan_Driver";
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static const char *default_serial_desc = "Lixuan OpenBox Series";
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static const char *default_dp_desc = "None";
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ofpmp_reply->type = htons(OFPMP_DESC);
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ofpmp_reply->flags = htonl(OFPMP_REPLY_MORE_NO);
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snprintf(ofpmp_reply->ofpmp_desc[0].mfr_desc, sizeof ofpmp_reply->ofpmp_desc[0].mfr_desc, "%s", default_mfr_desc);
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snprintf(ofpmp_reply->ofpmp_desc[0].hw_desc, sizeof ofpmp_reply->ofpmp_desc[0].hw_desc, "%s", default_hw_desc);
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snprintf(ofpmp_reply->ofpmp_desc[0].sw_desc, sizeof ofpmp_reply->ofpmp_desc[0].sw_desc, "%s", default_sw_desc);
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snprintf(ofpmp_reply->ofpmp_desc[0].serial_num, sizeof ofpmp_reply->ofpmp_desc[0].serial_num, "%s", default_serial_desc);
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snprintf(ofpmp_reply->ofpmp_desc[0].dp_desc, sizeof ofpmp_reply->ofpmp_desc[0].dp_desc, "%s", default_dp_desc);
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send_openflow_message(ofpbuf_reply, reply_len);
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return HANDLE;
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}
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```
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]
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=== 处理Flow Stats Request消息
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#para[
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`handle_ofpmsg_flow_stats`函数用于处理控制器发送的Flow Stats Request消息。该消息用于查询交换机的流表统计信息。函数生成一个Multipart Reply消息，并设置消息类型为Flow Stats。通过`send_openflow_message`函数将回复消息发送给控制器，并返回`HANDLE`表示消息已处理。
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```c
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static enum ofperr handle_ofpmsg_flow_stats(struct ofp_buffer *ofpbuf) {
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int reply_len = sizeof(struct ofp_header) + sizeof(struct ofp_multipart);
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struct ofp_buffer *reply_buffer = (struct ofp_buffer *)build_reply_ofpbuf(OFPT_MULTIPART_REPLY, ofpbuf->header.xid, reply_len);
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struct ofp_multipart *multipart_reply = (struct ofp_multipart *)reply_buffer->data;
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multipart_reply->type = htons(OFPMP_FLOW);
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multipart_reply->flags = htonl(OFPMP_REPLY_MORE_NO);
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send_openflow_message(reply_buffer, reply_len);
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return HANDLE;
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||||
}
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||||
```
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]
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=== 处理Aggregate Stats Request消息
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||||
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#para[
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||||
`handle_ofpmsg_aggregate`函数用于处理控制器发送的Aggregate Stats Request消息。该消息用于查询交换机的聚合统计信息。函数生成一个Multipart Reply消息，并填充聚合统计信息，如数据包计数、字节计数等。通过`send_openflow_message`函数将回复消息发送给控制器，并返回`HANDLE`表示消息已处理。
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```c
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static enum ofperr handle_ofpmsg_aggregate(struct ofp_buffer *ofpbuf) {
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int reply_len = sizeof(struct ofp_header) + sizeof(struct ofp_multipart) + sizeof(struct ofp_aggregate_stats_reply);
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struct ofp_buffer *ofpbuf_reply = (struct ofp_buffer *)build_reply_ofpbuf(OFPT_MULTIPART_REPLY, ofpbuf->header.xid, reply_len);
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struct ofp_multipart *ofpmp_reply = (struct ofp_multipart *)ofpbuf_reply->data;
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ofpmp_reply->type = htons(OFPMP_AGGREGATE);
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ofpmp_reply->flags = htonl(OFPMP_REPLY_MORE_NO);
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||||
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ofpmp_reply->ofpmp_aggregate_reply[0].packet_count = htonll(46);
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ofpmp_reply->ofpmp_aggregate_reply[0].byte_count = htonll(2025);
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||||
ofpmp_reply->ofpmp_aggregate_reply[0].flow_count = htonll(200);
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send_openflow_message(ofpbuf_reply, reply_len);
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||||
return HANDLE;
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||||
}
|
||||
```
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||||
]
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||||
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||||
=== 处理Table Stats Request消息
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||||
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||||
#para[
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||||
`handle_ofpmsg_table`函数用于处理控制器发送的Table Stats Request消息。该消息用于查询交换机的流表统计信息。函数生成一个Multipart Reply消息，并填充流表统计信息，如匹配计数、查找计数等。通过`send_openflow_message`函数将回复消息发送给控制器，并返回`HANDLE`表示消息已处理。
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||||
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||||
```c
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||||
static enum ofperr handle_ofpmsg_table(struct ofp_buffer *ofpbuf) {
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||||
int reply_len = sizeof(struct ofp_header) + sizeof(struct ofp_multipart) + sizeof(struct ofp_table_stats) * 1;
|
||||
struct ofp_buffer *ofpbuf_reply = (struct ofp_buffer *)build_reply_ofpbuf(OFPT_MULTIPART_REPLY, ofpbuf->header.xid, reply_len);
|
||||
struct ofp_multipart *ofpmp_reply = (struct ofp_multipart *)ofpbuf_reply->data;
|
||||
|
||||
ofpmp_reply->type = htons(OFPMP_TABLE);
|
||||
ofpmp_reply->flags = htonl(OFPMP_REPLY_MORE_NO);
|
||||
|
||||
ofpmp_reply->table_stats[0].matched_count = htonll(2025);
|
||||
ofpmp_reply->table_stats[0].table_id = 0;
|
||||
ofpmp_reply->table_stats[0].lookup_count = htonll(46);
|
||||
ofpmp_reply->table_stats[0].active_count = htonl(1);
|
||||
|
||||
send_openflow_message(ofpbuf_reply, reply_len);
|
||||
return HANDLE;
|
||||
}
|
||||
```
|
||||
]
|
||||
|
||||
=== 处理Port Stats Request消息
|
||||
|
||||
#para[
|
||||
`handle_ofpmsg_port_stats`函数用于处理控制器发送的Port Stats Request消息。该消息用于查询交换机的端口统计信息。函数生成一个Multipart Reply消息，并填充端口统计信息，如持续时间、接收数据包数等。通过`send_openflow_message`函数将回复消息发送给控制器，并返回`HANDLE`表示消息已处理。
|
||||
|
||||
```c
|
||||
static enum ofperr handle_ofpmsg_port_stats(struct ofp_buffer *ofpbuf) {
|
||||
int reply_len = sizeof(struct ofp_header) + sizeof(struct ofp_multipart) + sizeof(struct ofp_port_stats) * nmps.cnt;
|
||||
struct ofp_buffer *ofpbuf_reply = (struct ofp_buffer *)build_reply_ofpbuf(OFPT_MULTIPART_REPLY, ofpbuf->header.xid, reply_len);
|
||||
struct ofp_multipart *ofpmp_reply = (struct ofp_multipart *)ofpbuf_reply->data;
|
||||
|
||||
ofpmp_reply->type = htons(OFPMP_PORT_STATS);
|
||||
ofpmp_reply->flags = htonl(OFPMP_REPLY_MORE_NO);
|
||||
|
||||
for (int i = 0; i < nmps.cnt; i++) {
|
||||
ofpmp_reply->ofpmp_port_stats[i] = nmps.ports[i].stats;
|
||||
ofpmp_reply->ofpmp_port_stats[i].duration_sec = htonl(2025);
|
||||
ofpmp_reply->ofpmp_port_stats[i].duration_nsec = htonl(51);
|
||||
}
|
||||
|
||||
send_openflow_message(ofpbuf_reply, reply_len);
|
||||
return HANDLE;
|
||||
}
|
||||
```
|
||||
]
|
||||
|
||||
=== 处理Group Features Request消息
|
||||
|
||||
#para[
|
||||
`handle_ofpmsg_group_features`函数用于处理控制器发送的Group Features Request消息。该消息用于查询交换机的组表特性信息。函数生成一个Multipart Reply消息，并填充组表特性信息，如最大组数等。通过`send_openflow_message`函数将回复消息发送给控制器，并返回`HANDLE`表示消息已处理。
|
||||
|
||||
```c
|
||||
static enum ofperr handle_ofpmsg_group_features(struct ofp_buffer *ofpbuf) {
|
||||
int reply_len = sizeof(struct ofp_header) + sizeof(struct ofp_group_features) + 8;
|
||||
struct ofp_buffer *ofpbuf_reply = (struct ofp_buffer *)build_reply_ofpbuf(OFPT_MULTIPART_REPLY, ofpbuf->header.xid, reply_len);
|
||||
struct ofp_group_features *group = (struct ofp_group_features *)ofpbuf_reply->data;
|
||||
|
||||
group->types = htons(OFPMP_GROUP_FEATURES);
|
||||
group->max_groups[0] = htonl(0xdeadbeef);
|
||||
|
||||
send_openflow_message(ofpbuf_reply, reply_len);
|
||||
return HANDLE;
|
||||
}
|
||||
```
|
||||
]
|
||||
|
||||
=== 处理Port Description Request消息
|
||||
|
||||
#para[
|
||||
`handle_ofpmsg_port_desc`函数用于处理控制器发送的Port Description Request消息。该消息用于查询交换机的端口描述信息。函数生成一个Multipart Reply消息，并填充端口描述信息，如端口状态等。通过`send_openflow_message`函数将回复消息发送给控制器，并返回`HANDLE`表示消息已处理。
|
||||
|
||||
```c
|
||||
static enum ofperr handle_ofpmsg_port_desc(struct ofp_buffer *ofpbuf) {
|
||||
int reply_len = sizeof(struct ofp_header) + sizeof(struct ofp_multipart) + sizeof(struct ofp_port) * nmps.cnt;
|
||||
struct ofp_buffer *ofpbuf_reply = (struct ofp_buffer *)build_reply_ofpbuf(OFPT_MULTIPART_REPLY, ofpbuf->header.xid, reply_len);
|
||||
struct ofp_multipart *ofpmp_reply = (struct ofp_multipart *)ofpbuf_reply->data;
|
||||
|
||||
ofpmp_reply->type = htons(OFPMP_PORT_DESC);
|
||||
ofpmp_reply->flags = htonl(OFPMP_REPLY_MORE_NO);
|
||||
|
||||
for (int i = 0; i < nmps.cnt; i++) {
|
||||
ofpmp_reply->ofpmp_port_desc[i] = nmps.ports[i].state;
|
||||
}
|
||||
|
||||
send_openflow_message(ofpbuf_reply, reply_len);
|
||||
return HANDLE;
|
||||
}
|
||||
```
|
||||
]
|
||||
|
||||
=== 处理Packet Out消息
|
||||
|
||||
#para[
|
||||
`handle_ofpmsg_packet_out`函数用于处理控制器发送的Packet Out消息。该消息用于指示交换机将数据包从指定端口发送出去。函数解析消息中的动作列表，判断动作类型是否为`OFPAT_OUTPUT`，并根据动作指示的端口号调用`nms_exec_action`函数将数据包发送出去。函数返回`HANDLE`表示消息已处理。
|
||||
|
||||
```c
|
||||
static enum ofperr handle_ofpmsg_packet_out(struct ofp_buffer *ofpbuf) {
|
||||
struct ofp_packet_out *out = (struct ofp_packet_out *)ofpbuf;
|
||||
struct ofp_action_output *action = (struct ofp_action_output *)&out->actions[0];
|
||||
int action_len = ntohs(out->actions_len);
|
||||
struct eth_header *eth = (struct eth_header *)&ofpbuf->data[sizeof(struct ofp_packet_out) - sizeof(struct ofp_header) + action_len];
|
||||
int send_len = ntohs(ofpbuf->header.length) - sizeof(struct ofp_packet_out) - action_len;
|
||||
|
||||
if (action_len == 0) {
|
||||
nms_exec_action(ntohl(out->in_port), OFPP_FLOOD, eth, send_len, -1);
|
||||
} else {
|
||||
while (action_len > 0) {
|
||||
if (action->type == OFPAT_OUTPUT) {
|
||||
nms_exec_action(ntohl(out->in_port), ntohl(action->port), eth, send_len, -1);
|
||||
}
|
||||
action_len -= sizeof(struct ofp_action_output);
|
||||
action++;
|
||||
}
|
||||
}
|
||||
return HANDLE;
|
||||
}
|
||||
```
|
||||
]
|
||||
|
||||
=== 处理Role Request消息
|
||||
|
||||
#para[
|
||||
`handle_opfmsg_role_request`函数用于处理控制器发送的Role Request消息。该消息用于配置交换机的角色（如主控制器、从控制器等）。函数生成一个Role Reply消息，并填充角色配置信息。通过`send_openflow_message`函数将回复消息发送给控制器，并返回`HANDLE`表示消息已处理。
|
||||
|
||||
```c
|
||||
static enum ofperr handle_opfmsg_role_request(struct ofp_buffer *ofpbuf) {
|
||||
int reply_len = sizeof(struct ofp_header) + sizeof(struct ofp_role);
|
||||
struct ofp_buffer *ofpbuf_reply = (struct ofp_buffer *)build_reply_ofpbuf(OFPT_ROLE_REPLY, ofpbuf->header.xid, reply_len);
|
||||
memcpy(ofpbuf_reply->data, ofpbuf->data, sizeof(struct ofp_role));
|
||||
ofpbuf_reply->header.type = OFPT_ROLE_REPLY;
|
||||
|
||||
send_openflow_message(ofpbuf_reply, reply_len);
|
||||
return HANDLE;
|
||||
}
|
||||
```
|
||||
]
|
||||
== 实验结果
|
||||
#para[
|
||||
在控制器与交换机之间进行抓包，分析报文的交互过程。控制器发送不同类型的OpenFlow消息给交换机，交换机接收并处理消息，并返回相应的回复消息。通过抓包分析，可以看到消息的交互过程，包括消息头、消息类型、消息长度等字段的解析和处理。用这种方式来验证协议编写的正确性。
|
||||
|
||||
实现的子协议种类较多，这里只展示部分报文内容。
|
||||
]
|
||||
=== OFPT_ROLE_REPLY
|
||||
#para[
|
||||
+ OFPT_ROLE_REPLY类型消息。此消息用于配置交换机的角色（如主控制器、从控制器等）。下面的@slave_request 是控制器发送的Role Request消息。
|
||||
#figure(image("slave.png",fit:"stretch",format:"png"),caption:"OFPT_ROLE_REQUEST消息",)<slave_request>
|
||||
如图@slave_reply 所示，交换机接收并处理后返回的Role Reply消息。
|
||||
#figure(image("slave_reply.png",fit:"stretch",format:"png"),caption:"OFPT_ROLE_REPLY消息",)<slave_reply>
|
||||
这说明交换机已经接收到了控制器发送的Role Request消息，并返回了Role Reply消息。
|
||||
]
|
||||
=== OFPT_MULTIPART_REPLY
|
||||
#para[
|
||||
+ OFPMP_DESC类型消息。此消息用于查询交换机的描述信息，包括制造商、硬件版本、软件版本、序列号和数据路径描述等。
|
||||
#figure(image("lixuanwang.png",fit:"stretch",format:"png"),caption:"OFPMP_DESC消息",)
|
||||
可以看到图中的消息包含了制造商、硬件版本、软件版本、序列号和数据路径描述等信息（此处使用了自己的信息进行标记与区分）。
|
||||
+ OFPMP_TABLE类型消息。此消息用于查询交换机的流表统计信息，包括匹配计数、查找计数等。
|
||||
#figure(image("table.png",fit:"stretch",format:"png"),caption:"OFPMP_TABLE消息",)
|
||||
可以看到图中的消息包含了匹配计数、查找计数等信息（此处修改为了自己设置的值）。
|
||||
]
|
||||
= 实验总结
|
||||
#para[
|
||||
|
||||
]
|
||||
#show heading: it => box(width: 100%)[
|
||||
#v(0.50em)
|
||||
#set text(font: hei)
|
||||
// #counter(heading).display()
|
||||
// #h(0.5em)
|
||||
#it.body
|
||||
]
|
||||
#pagebreak()
|
||||
#bibliography("ref.yml",full: true,title: "参考文献",style:"gb-7714-2015-numeric")
|
||||
|
||||
|
||||
/*
|
||||
根据这个网站的格式示范https://github.com/typst/hayagriva/blob/main/docs/file-format.md
|
||||
为这些网页生成.yml文件
|
||||
https://opennetworking.org/wp-content/uploads/2014/10/openflow-spec-v1.3.0.pdf
|
||||
https://www.cnblogs.com/goldsunshine/p/7262484.html
|
||||
https://www.jianshu.com/p/acfeae1771b3
|
||||
https://www.jianshu.com/p/82e238eb8d14
|
||||
*/
|
||||
Reference in New Issue
Block a user