diff --git a/tcpip/ilist/list.go b/tcpip/ilist/list.go
new file mode 100644
index 0000000..b292e85
--- /dev/null
+++ b/tcpip/ilist/list.go
@@ -0,0 +1,150 @@
+// 包 ilist 提供了侵入式链表的实现
+package ilist
+
+type Linker interface {
+	Next() Element
+	Prev() Element
+	SetNext(Element)
+	SetPrev(Element)
+}
+
+type Element interface {
+	Linker
+}
+
+// ElementMapper 默认提供身份映射。
+// 如果它们不相同，则可以替换它以提供将元素映射到链接器对象的结构。
+// 在以下情况下通常不需要 ElementMapper：Linker 保持原样，Element 保持原样，
+// 或者 Linker 和 Element 是相同类型
+type ElementMapper struct{}
+
+// linkerFor maps an Element to a Linker.
+// This default implementation should be inline 1d
+func (ElementMapper) linkerFor(elem Element) Linker {
+	return elem
+}
+
+type List struct {
+	head Element
+	tail Element
+}
+
+func (l *List) Reset() {
+	l.head = nil
+	l.tail = nil
+}
+
+func (l *List) Empty() bool {
+	return l.head == nil
+}
+
+func (l *List) Front() Element {
+	return l.head
+}
+
+func (l *List) Back() Element {
+	return l.tail
+}
+
+func (l *List) PushFront(e Element) {
+	ElementMapper{}.linkerFor(e).SetPrev(nil)
+	ElementMapper{}.linkerFor(e).SetNext(l.head) //当前头部作为新头部的下一个节点
+
+	if l.head != nil {
+		ElementMapper{}.linkerFor(l.head).SetPrev(e)
+	} else {
+		l.tail = e
+	}
+	l.head = e
+}
+
+func (l *List) PushBack(e Element) {
+	ElementMapper{}.linkerFor(e).SetPrev(l.tail) // 当前尾部作为新尾部的上一个节点
+	ElementMapper{}.linkerFor(e).SetNext(nil)
+
+	if l.tail != nil {
+		ElementMapper{}.linkerFor(l.tail).SetNext(e)
+	} else {
+		l.head = e
+	}
+	l.tail = e
+}
+
+// 将m尾插到l,然后清除m
+func (l *List) PushBackList(m *List) {
+	// 如果没有
+	if l.head == nil {
+		l.head = m.head
+		l.tail = m.tail
+	} else {
+		ElementMapper{}.linkerFor(l.tail).SetNext(m.head)
+		ElementMapper{}.linkerFor(m.head).SetPrev(l.tail)
+		l.tail = m.tail
+	}
+	m.head = nil
+	m.tail = nil
+}
+
+func (l *List) InsertAfter(b, e Element) {
+	a := ElementMapper{}.linkerFor(b).Next()
+	ElementMapper{}.linkerFor(e).SetNext(a)
+	ElementMapper{}.linkerFor(e).SetPrev(b)
+	ElementMapper{}.linkerFor(b).SetNext(e)
+
+	if a != nil {
+		ElementMapper{}.linkerFor(a).SetPrev(e)
+	} else {
+		l.tail = e
+	}
+}
+
+func (l *List) InsertBefore(a, e Element) {
+	b := ElementMapper{}.linkerFor(a).Prev()
+	ElementMapper{}.linkerFor(e).SetPrev(b)
+	ElementMapper{}.linkerFor(e).SetNext(a)
+	ElementMapper{}.linkerFor(a).SetPrev(e)
+
+	if b != nil {
+		ElementMapper{}.linkerFor(b).SetNext(e)
+	} else {
+		l.head = e
+	}
+}
+
+func (l *List) Remove(e Element) {
+	prev := ElementMapper{}.linkerFor(e).Prev()
+	next := ElementMapper{}.linkerFor(e).Next()
+
+	if prev != nil {
+		ElementMapper{}.linkerFor(prev).SetNext(next)
+	} else {
+		l.tail = next
+	}
+
+	if next != nil {
+		ElementMapper{}.linkerFor(next).SetPrev(prev)
+	} else {
+		l.tail = prev
+	}
+}
+
+type Entry struct {
+	next Element
+	prev Element
+}
+
+func (e *Entry) Next() Element {
+	return e.next
+}
+
+func (e *Entry) Prev() Element {
+	return e.prev
+}
+
+func (e *Entry) SetNext(elem Element) {
+	e.next = elem
+}
+
+func (e *Entry) SetPrev(elem Element) {
+	e.prev = elem
+}
diff --git a/tcpip/link/fdbased/endpoint.go b/tcpip/link/fdbased/endpoint.go
index ef0764d..86a9157 100644
--- a/tcpip/link/fdbased/endpoint.go
+++ b/tcpip/link/fdbased/endpoint.go
@@ -38,9 +38,6 @@ type endpoint struct {
 	views      []buffer.View
 	dispatcher stack.NetworkDispatcher
 
-	// handleLocal indicates whether packets destined to itself should be
-	// handled by the netstack internally (true) or be forwarded to the FD
-	// endpoint (false).
 	// handleLocal指示发往自身的数据包是由内部netstack处理（true）还是转发到FD端点（false）。
 	// Resend packets back to netstack if destined to itself
 	// Add option to redirect packet back to netstack if it's destined to itself.
diff --git a/tcpip/seqnum/seqnum.go b/tcpip/seqnum/seqnum.go
new file mode 100644
index 0000000..713f5a5
--- /dev/null
+++ b/tcpip/seqnum/seqnum.go
@@ -0,0 +1,8 @@
+// 包 seqnum 定义了 TCP 序列号的类型和方法，以便它们适合 32 位字并在发生溢出时正常工作
+package seqnum
+
+// 一个序列号的值
+type Value uint32
+
+// size表示一个序号窗口的大小（长度）
+type Size uint32
diff --git a/tcpip/stack/nic.go b/tcpip/stack/nic.go
index c1e0d48..6348305 100644
--- a/tcpip/stack/nic.go
+++ b/tcpip/stack/nic.go
@@ -4,6 +4,7 @@ import (
 	"sync"
 
 	"github.com/impact-eintr/netstack/tcpip"
+	"github.com/impact-eintr/netstack/tcpip/ilist"
 )
 
 type referencedNetworkEndpoint struct {
@@ -33,7 +34,24 @@ type NIC struct {
 	promiscuous bool
 	primary     map[tcpip.NetworkProtocolNumber]*ilist.List
 	// 网络层端的记录
-	endpoints map[tcpip.NetworkEndpointID]*referencedNetworkEndpoint
+	endpoints map[NetworkEndpointID]*referencedNetworkEndpoint
 	// 子网的记录
 	subnets []tcpip.Subnet
 }
+
+// 根据参数新建一个NIC
+func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint) *NIC {
+	return &NIC{
+		stack:     stack,
+		id:        id,
+		name:      name,
+		linkEP:    ep,
+		demux:     newTransportDemuxer(stack),
+		primary:   make(map[tcpip.NetworkProtocolNumber]*ilist.List),
+		endpoints: make(map[NetworkEndpointID]*referencedNetworkEndpoint),
+	}
+}
+
+type NetworkEndpointID struct {
+	LocalAddress tcpip.Address
+}
diff --git a/tcpip/stack/stack.go b/tcpip/stack/stack.go
index 9b15899..941c8be 100644
--- a/tcpip/stack/stack.go
+++ b/tcpip/stack/stack.go
@@ -2,10 +2,12 @@ package stack
 
 import (
 	"sync"
+	"time"
 
 	"github.com/impact-eintr/netstack/tcpip"
 	"github.com/impact-eintr/netstack/tcpip/buffer"
 	"github.com/impact-eintr/netstack/tcpip/ports"
+	"github.com/impact-eintr/netstack/tcpip/seqnum"
 )
 
 type transportProtocolState struct {
@@ -45,4 +47,42 @@ type TCPProbeFunc func(s TCPEndpointState)
 
 // TCPEndpointState 是 TCP 端点内部状态的副本
 type TCPEndpointState struct {
+	ID         TCPEndpointID // ID 是端点的 TransportEndpointID 的副本
+	SegTime    time.Time     // SegTime 表示收到该段的绝对时间
+	RcvBufSize int           // RcvBufSize 是端点的接收套接字缓冲区的大小
+	RcvBufUsed bool          // RcvBufUsed 是端点的接收套接字缓冲区中实际保存的字节数
+	RcvClosed  bool          // RcvClosed 如果为真，表示端点已经关闭读取
+	SendTSOk   bool          // SendOk 用于指示何时协商了 TS 选项。当 sendOk 为真时，每个非 RST 段都应根据 RFC 7323#section-1.1 携带 TS
+
+	// 应该在时间戳的TSEcr 字段中为端点发送的未来段发送的时间戳。当此端点接收到新段时，如果需要，将更新此字段
+	RecentTS uint32
+	// TSOffset 是添加到时间戳选项中 TSVal 字段值的随机偏移量
+	TSOffset uint32
+
+	// 如果对等方在 SYN/SYN-ACK 中发送 TCPSACKPermitted 选项，则 SACKPermitted 设置为 true
+	SACKPermitted bool
+	SACK          TCPSACKInfo // SACK 保存该端点的 TCP SACK 相关信息
+	SndBufSize    int         // SndBufSize 是套接字发送缓冲区的大小
+	SndBufUsed    bool        // SndBufUsed 是端点的发送套接字缓冲区中实际发送的字节数
+	SndClosed     bool        // SndClosed 表示端点已关闭发送
+
+	sndBufInQueue seqnum.Size // SndBufInQueue 是发送队列中的字节数
+
+	// PacketTooBigCount 用于通知主协程收到“数据包太大”控制数据包的次数
+	PacketTooBigCount int
+
+	SndMTU   int // SndMTU 是在收到的控制数据包中看到的最小 MTU
+	Receiver TCPReceiverState
+	Sender   TCPSenderState
+}
+
+type TCPReceiverState struct {
+}
+
+type TCPSenderState struct {
+}
+
+// 根据nic id和linkEP id来创建和注册一个网卡对象
+func (s *Stack) CreateNIC(id tcpip.NICID, linkEP tcpip.LinkEndpointID) *tcpip.Error {
+	return s.createNIC(id, "", linkEP, true)
 }