Главная
Клипы
Новинки
Тренды
Популярные
Лайки
Комментарии
Все категории
Музыка
Фильмы
Видеоигры
Транспорт
Животные
Спорт
Путешествия
Люди и блоги
Юмор
Развлечения
Политика
Хобби
Образование
Наука
Организации
Найти
What is a Network Protocol
MYTHICAL HACKER
193 подписчика
Скачать
200 видео с канала:
MYTHICAL HACKER
What is a Network Protocol
Скачать
1 A First Look At Routing
Скачать
6 The Joy Of VLANs
Скачать
16 VTP Fundamentals
Скачать
2 The Dawn Of Switching
Скачать
17 Resetting The Revision Number Whats The Big Deal
Скачать
8 Port Security Secure MAC Addresses
Скачать
3 Building A MAC Address Table The Smart Way
Скачать
7 The Cisco Switching Model and Intro To Port Security
Скачать
14 Trunking Labs and Modes
Скачать
5 How They Get There Frame Forwarding Methods
Скачать
4 Let The Switch Do The Work Dynamic MAC Address Table Entries
Скачать
9 Port Security Sticky MAC Addresses
Скачать
1 Hubs And Repeaters Why Are We Still Talking About These
Скачать
10 Combining Secure and Sticky MAC Addresses
Скачать
15 Drawing The Line Allowing and Disallowing VLANs
Скачать
11 Spanning Tree Protocol Fundamentals
Скачать
13 Trunking Fundamentals
Скачать
12 What DO Those Lights Mean
Скачать
1 Duplexes Suplexes and Autonegotiation
Скачать
3 Formats and Rollover Cables
Скачать
4 Bonus Video Show Interface Ethernet
Скачать
2 Cabling Types and Standards
Скачать
2 Networking Layer Interaction And More
Скачать
1 Networking Fundamentals And The OSI Model
Скачать
3 Fundamentals of Network Troubleshooting and Models
Скачать
4 The Fight Of The Century TCP vs UDP
Скачать
5 More TCP UDP and Port Numbers
Скачать
204 BGP 19 Prefix Lists End
Скачать
191 BGP 6 Origin and Next Hop Attributes
Скачать
199 BGP 14 More Weight Work
Скачать
203 BGP 18 Prefix Lists Begin
Скачать
200 BGP 15 Route Summarization
Скачать
187 BGP 2 External BGP Peerings
Скачать
190 BGP 5 Advertising Routes with Network
Скачать
194 BGP 9 The Next Hop Address Rule
Скачать
195 BGP 10 The Multi Exit Discriminator MED
Скачать
205 BGP 20 Some Final Words
Скачать
185 Read This Before You Start The BGP Section
Скачать
188 BGP 3 iBGP Peering and Loopback Interfaces
Скачать
193 BGP 8 Next Hop Addresses
Скачать
202 BGP 17 Route Reflectors
Скачать
198 BGP 13 The Weight Attribute
Скачать
201 BGP 16 Synch Rules and the Full Mesh
Скачать
197 BGP 12 Local Preferences Changing One But Not All
Скачать
186 BGP 1 Introduction
Скачать
192 BGP 7 The Best Path Selection Process
Скачать
189 BGP 4 eBGP Peering with Loopback Interfaces
Скачать
196 BGP 11 Local Pref All Or Nothing At All
Скачать
181 OSPF 19 ABRs ASBRs And Other Router Types
Скачать
178 OSPF 16 New Router In Network Using The Default Option
Скачать
182 OSPF 20 The Default Information Originate Command
Скачать
179 OSPF 17 Stub Areas
Скачать
180 OSPF 18 Total Stub Areas
Скачать
177 OSPF 15 Verifying Your Passive Interfaces
Скачать
176 OSPF 14 Cutting Down On Overhead w Passive Interfaces
Скачать
175 OSPF 13 Virtual Link Build
Скачать
184 OSPF 22 More Port Cost Calculation Plus Changing The Cost At The Interface
Скачать
183 OSPF 21 Changing The Port Cost Calculation
Скачать
163 OSPF 2 LSAs and Adjacencies
Скачать
162 OSPF 1 Intro To Link State Protocols
Скачать
165 OSPF 4 Hello and Dead Timers
Скачать
173 OSPF 11
Скачать
168 OSPF 7 Why Areas PLUS OSPF Not Starting
Скачать
169 OSPF 8 Broadcast Network Build
Скачать
166 OSPF 5 The Adjacency States
Скачать
172 OSPF 10 RID Fix Pings and Shows
Скачать
167 OSPF 6 The DR BDR and RID
Скачать
170 OSPF 11 Point to Point Network Build
Скачать
171 OSPF 9 NBMA Network Build
Скачать
174 OSPF 12 Broadcast Network Build Somethings Missing
Скачать
164 OSPF 3 Network Mask Match Yes Or No
Скачать
161 RSTP 3 More Lab Work
Скачать
160 RSTP 2 Edge Ports and Lab Work
Скачать
159 RSTP 1 It Begins
Скачать
157 EC 3 The Verification
Скачать
158 EC 4 The Negotiation
Скачать
155 EC 1 The Theory
Скачать
156 EC 2 The Configuration
Скачать
150 STP 12 Choosing Your Roots
Скачать
140 STP 2 Switching Loops and More Fundamentals
Скачать
143 STP 5 Root Bridge Election Results Non Root Bridge
Скачать
154 STP 16 BPDU Guard
Скачать
146 STP 8 Root Port Tiebreakers
Скачать
153 STP 15 Root Guard
Скачать
141 STP 3 Root Bridge Election Walkthrough
Скачать
149 STP 11 Per VLAN Load Balancing
Скачать
139 STP 1 The Fundamentals
Скачать
148 STP 10 Speed Changes and Port Costs
Скачать
144 STP 6 STP Timer Changes
Скачать
151 STP 13 Choosing Your Secondary Roots
Скачать
145 STP 7 Root Path Cost vs Port Cost
Скачать
152 STP 14 Stone Cold Priority and PortFast
Скачать
147 STP 9 DP Selection on Non Root Switches
Скачать
142 STP 4 Root Bridge Election Results Root Bridge
Скачать
138 VTP 9 Pruning and Real World V3 Tips
Скачать
137 VTP 8 More On The VTP Password
Скачать
136 VTP 7 The VTP Password
Скачать
135 VTP 6 CRN Lab Fully Initializing The Switch
Скачать
134 VTP 5 The Config Revision Number
Скачать
133 VTP 4 The Modes
Скачать
130 VTP 1 Why Do We Need It
Скачать
132 VTP 3 The Mysterious Joins
Скачать
131 VTP 2 Lab Continues
Скачать
123 TNT 5 Where ARE My Log Messages
Скачать
127 TNT 9 The Link Layer Discovery Protocol LLDP
Скачать
117 IPV6 17 Default and Host Static Routes
Скачать
114 IPV6 14 Static Routes Recursive and Directly Connected
Скачать
129 TNT 11 A Little More Config Register Work
Скачать
122 TNT 4 Buffer and Syslog Logging
Скачать
126 TNT 8 More Fun With CDP
Скачать
112 IPV6 12 The IPV6 Routing Table
Скачать
115 IPV6 15 Static Routes Fully Specified
Скачать
088 ACL 9 Telnet and Extended ACLs
Скачать
098 NAT 2 Static NAT Lab
Скачать
108 IPV6 8 Router Discovery With NDP
Скачать
111 IP 11 Smart Stuff Our DAD Says
Скачать
087 ACL 8 Named Extended ACL Lab
Скачать
095 NTP 3 Peering Lab
Скачать
119 TNT 1 Timestamps
Скачать
089 ACL 10 Telnet Extended ACLs and Time Ranges
Скачать
124 TNT 6 Banners
Скачать
100 NAT 4 Port Address Translation Lab
Скачать
106 IPv6 Calculating the Interface Identifier
Скачать
120 TNT 2 The Password Encryption Services
Скачать
125 TNT 7 CDP Fundamentals
Скачать
105 IPV6 5 Link Local Addresses
Скачать
118 IPV6 18 Nuts Bolts and Frame Format Comparison
Скачать
107 IPV6 7 Using The Interface Identifier as Host Address
Скачать
099 NAT 3 Dynamic NAT Lab
Скачать
113 IPV6 13 Pinging IPV6 Addresses
Скачать
094 NTP 2 Server Client Lab
Скачать
096 NTP 4 Broadcast Mode
Скачать
110 IPV6 10 DHCP On Planet IPV6
Скачать
102 IPV6 2 The Global Routing Prefix and Subnet ID
Скачать
101 IPV6 1 Curing Address Anxiety With Compression
Скачать
103 IPV6 3 Enabling V6 Twice
Скачать
090 ACL 11 Sequence Numbers Telnet and Extended ACLs
Скачать
128 TNT 10 Cisco Password Recovery Procedures
Скачать
097 NAT 1 The Fundamentals of NAT and PAT
Скачать
109 IPV6 9 Host Discovery With NDP
Скачать
091 ACL 12 One More Telnet Test plus Absolute Time Ranges
Скачать
116 IPV6 16 Using The Link Local Address With Static Routes
Скачать
093 NTP 1 Whats Going On
Скачать
092 ACL 13 Where To Put It and Why
Скачать
104 IPV6 4 Configuring And Verifying IPV6 Addresses
Скачать
121 TNT 3 Console Logging
Скачать
086 ACL 7 Named Standard ACL Lab
Скачать
085 ACL 6 Host Any and The Order Of The Lines
Скачать
084 ACL 5 Extended ACL Lab
Скачать
083 ACL 4 Standard ACL Lab Concludes
Скачать
082 ACL 3 Standard ACL Lab Begins
Скачать
081 ACL 2 Wildcard Masks Made Easy
Скачать
080 ACL 1 Access List Rules
Скачать
079 10 Subnetting
Скачать
078 Subnet 9 Determining The Broadcast Address and Valid Address Range
Скачать
077 Subnet 8 Finding The Subnet Of An IP Address
Скачать
076 Subnet 7 Number Of Valid Hosts
Скачать
075 Subnet 6 Number Of Valid Subnets Bulldog Approach
Скачать
074 Subnet 5 Number Of Valid Subnets Classic Approach
Скачать
073 Subnet 4 Binary to Decimal Conversions
Скачать
072 Subnet 3 Decimal to Binary Conversions Dotted Decimal Example
Скачать
071 Subnet 2 Decimal to Binary Conversions Single Value Example
Скачать
070 Subnet 1 The Whys Ins and Outs of Subnetting
Скачать
069 Sec 1115 Originating A Default Route With RIP
Скачать
068 Sec 1114 Floating Static Route Lab Continues
Скачать
067 Sec 1113 Floating Static Route Lab Begins
Скачать
066 Sec 1112 Version Mismatches and Debugging Tips
Скачать
065 Sec 1111 More RIP Load Balancing Intro To Traceroute
Скачать
064 Sec 1110 Fun With RIP Load Balancing
Скачать
063 Sec 119 Administrative Distances
Скачать
062 Sec 118 Passive Interfaces
Скачать
061 Sec 117 The Cure for Autosummarization
Скачать
060 Sec 116 The Dangers of Autosummarization
Скачать
059 Sec 115 RIP Lab Concludes
Скачать
058 Sec 114 RIP Lab Continues
Скачать
057 Sec 113 RIP Lab Begins
Скачать
056 Sec 112 Split Horizon and Poison Reverse
Скачать
055 Sec 111 Intro To Distance Vector Protocols
Скачать
054 Sec 105 Default Routes Are Beautiful Sometimes
Скачать
053 Sec 104 Lab Continues Default Static Routing
Скачать
052 Sec 103 Lab Continues Host Static Routing
Скачать
051 Sec 102 Lab Continues Intro To Debug IP Packet
Скачать
050 Sec 101 Lab Topology Pings And HAS Networking
Скачать
049 Sec 92 DHCP Fundamentals
Скачать
048 Sec 91 DNS And ARP
Скачать
047 Sec 83 Multiplexing and Intro To Port Numbers
Скачать
046 Sec 82 The Comparison Continues
Скачать
045 Sec 81 TCP Good UDP Bad
Скачать
044 Sec 77 The Description and Interface Range Commands
Скачать
043 Sec 76 Slashes and Console Port Options
Скачать
042 Sec 75 Autonegotiation
Скачать
041 Sec 74 Telnet Labs End
Скачать
040 Sec 73 Telnet Labs Begin
Скачать
039 Sec 72 Creating A Non Default SVI
Скачать
038 Sec 71 Introduction To SVIs
Скачать
036 Routing 4 Connected Routes Walkthrough
Скачать
037 Routing 5 Static Route Walkthrough
Скачать
033 Routing 1 IP Addresses Subnet Masks and Binary Conversions
Скачать
035 Routing 3 The Private IP Address Classes
Скачать
Канал: MYTHICAL HACKER
What is a Network Protocol
Скачать
1 A First Look At Routing
Скачать
6 The Joy Of VLANs
Скачать
16 VTP Fundamentals
Скачать
2 The Dawn Of Switching
Скачать
17 Resetting The Revision Number Whats The Big Deal
Скачать
8 Port Security Secure MAC Addresses
Скачать
3 Building A MAC Address Table The Smart Way
Скачать
7 The Cisco Switching Model and Intro To Port Security
Скачать
14 Trunking Labs and Modes
Скачать
5 How They Get There Frame Forwarding Methods
Скачать
4 Let The Switch Do The Work Dynamic MAC Address Table Entries
Скачать
9 Port Security Sticky MAC Addresses
Скачать
1 Hubs And Repeaters Why Are We Still Talking About These
Скачать
10 Combining Secure and Sticky MAC Addresses
Скачать
15 Drawing The Line Allowing and Disallowing VLANs
Скачать
11 Spanning Tree Protocol Fundamentals
Скачать
13 Trunking Fundamentals
Скачать
12 What DO Those Lights Mean
Скачать
1 Duplexes Suplexes and Autonegotiation
Скачать
3 Formats and Rollover Cables
Скачать
4 Bonus Video Show Interface Ethernet
Скачать
2 Cabling Types and Standards
Скачать
2 Networking Layer Interaction And More
Скачать
1 Networking Fundamentals And The OSI Model
Скачать
3 Fundamentals of Network Troubleshooting and Models
Скачать
4 The Fight Of The Century TCP vs UDP
Скачать
5 More TCP UDP and Port Numbers
Скачать
204 BGP 19 Prefix Lists End
Скачать
191 BGP 6 Origin and Next Hop Attributes
Скачать
199 BGP 14 More Weight Work
Скачать
203 BGP 18 Prefix Lists Begin
Скачать
200 BGP 15 Route Summarization
Скачать
187 BGP 2 External BGP Peerings
Скачать
190 BGP 5 Advertising Routes with Network
Скачать
194 BGP 9 The Next Hop Address Rule
Скачать
195 BGP 10 The Multi Exit Discriminator MED
Скачать
205 BGP 20 Some Final Words
Скачать
185 Read This Before You Start The BGP Section
Скачать
188 BGP 3 iBGP Peering and Loopback Interfaces
Скачать
193 BGP 8 Next Hop Addresses
Скачать
202 BGP 17 Route Reflectors
Скачать
198 BGP 13 The Weight Attribute
Скачать
201 BGP 16 Synch Rules and the Full Mesh
Скачать
197 BGP 12 Local Preferences Changing One But Not All
Скачать
186 BGP 1 Introduction
Скачать
192 BGP 7 The Best Path Selection Process
Скачать
189 BGP 4 eBGP Peering with Loopback Interfaces
Скачать
196 BGP 11 Local Pref All Or Nothing At All
Скачать
181 OSPF 19 ABRs ASBRs And Other Router Types
Скачать
178 OSPF 16 New Router In Network Using The Default Option
Скачать
182 OSPF 20 The Default Information Originate Command
Скачать
179 OSPF 17 Stub Areas
Скачать
180 OSPF 18 Total Stub Areas
Скачать
177 OSPF 15 Verifying Your Passive Interfaces
Скачать
176 OSPF 14 Cutting Down On Overhead w Passive Interfaces
Скачать
175 OSPF 13 Virtual Link Build
Скачать
184 OSPF 22 More Port Cost Calculation Plus Changing The Cost At The Interface
Скачать
183 OSPF 21 Changing The Port Cost Calculation
Скачать
163 OSPF 2 LSAs and Adjacencies
Скачать
162 OSPF 1 Intro To Link State Protocols
Скачать
165 OSPF 4 Hello and Dead Timers
Скачать
173 OSPF 11
Скачать
168 OSPF 7 Why Areas PLUS OSPF Not Starting
Скачать
169 OSPF 8 Broadcast Network Build
Скачать
166 OSPF 5 The Adjacency States
Скачать
172 OSPF 10 RID Fix Pings and Shows
Скачать
167 OSPF 6 The DR BDR and RID
Скачать
170 OSPF 11 Point to Point Network Build
Скачать
171 OSPF 9 NBMA Network Build
Скачать
174 OSPF 12 Broadcast Network Build Somethings Missing
Скачать
164 OSPF 3 Network Mask Match Yes Or No
Скачать
161 RSTP 3 More Lab Work
Скачать
160 RSTP 2 Edge Ports and Lab Work
Скачать
159 RSTP 1 It Begins
Скачать
157 EC 3 The Verification
Скачать
158 EC 4 The Negotiation
Скачать
155 EC 1 The Theory
Скачать
156 EC 2 The Configuration
Скачать
150 STP 12 Choosing Your Roots
Скачать
140 STP 2 Switching Loops and More Fundamentals
Скачать
143 STP 5 Root Bridge Election Results Non Root Bridge
Скачать
154 STP 16 BPDU Guard
Скачать
146 STP 8 Root Port Tiebreakers
Скачать
153 STP 15 Root Guard
Скачать
141 STP 3 Root Bridge Election Walkthrough
Скачать
149 STP 11 Per VLAN Load Balancing
Скачать
139 STP 1 The Fundamentals
Скачать
148 STP 10 Speed Changes and Port Costs
Скачать
144 STP 6 STP Timer Changes
Скачать
151 STP 13 Choosing Your Secondary Roots
Скачать
145 STP 7 Root Path Cost vs Port Cost
Скачать
152 STP 14 Stone Cold Priority and PortFast
Скачать
147 STP 9 DP Selection on Non Root Switches
Скачать
142 STP 4 Root Bridge Election Results Root Bridge
Скачать
138 VTP 9 Pruning and Real World V3 Tips
Скачать
137 VTP 8 More On The VTP Password
Скачать
136 VTP 7 The VTP Password
Скачать
135 VTP 6 CRN Lab Fully Initializing The Switch
Скачать
134 VTP 5 The Config Revision Number
Скачать
133 VTP 4 The Modes
Скачать
130 VTP 1 Why Do We Need It
Скачать
132 VTP 3 The Mysterious Joins
Скачать
131 VTP 2 Lab Continues
Скачать
123 TNT 5 Where ARE My Log Messages
Скачать
127 TNT 9 The Link Layer Discovery Protocol LLDP
Скачать
117 IPV6 17 Default and Host Static Routes
Скачать
114 IPV6 14 Static Routes Recursive and Directly Connected
Скачать
129 TNT 11 A Little More Config Register Work
Скачать
122 TNT 4 Buffer and Syslog Logging
Скачать
126 TNT 8 More Fun With CDP
Скачать
112 IPV6 12 The IPV6 Routing Table
Скачать
115 IPV6 15 Static Routes Fully Specified
Скачать
088 ACL 9 Telnet and Extended ACLs
Скачать
098 NAT 2 Static NAT Lab
Скачать
108 IPV6 8 Router Discovery With NDP
Скачать
111 IP 11 Smart Stuff Our DAD Says
Скачать
087 ACL 8 Named Extended ACL Lab
Скачать
095 NTP 3 Peering Lab
Скачать
119 TNT 1 Timestamps
Скачать
089 ACL 10 Telnet Extended ACLs and Time Ranges
Скачать
124 TNT 6 Banners
Скачать
100 NAT 4 Port Address Translation Lab
Скачать
106 IPv6 Calculating the Interface Identifier
Скачать
120 TNT 2 The Password Encryption Services
Скачать
125 TNT 7 CDP Fundamentals
Скачать
105 IPV6 5 Link Local Addresses
Скачать
118 IPV6 18 Nuts Bolts and Frame Format Comparison
Скачать
107 IPV6 7 Using The Interface Identifier as Host Address
Скачать
099 NAT 3 Dynamic NAT Lab
Скачать
113 IPV6 13 Pinging IPV6 Addresses
Скачать
094 NTP 2 Server Client Lab
Скачать
096 NTP 4 Broadcast Mode
Скачать
110 IPV6 10 DHCP On Planet IPV6
Скачать
102 IPV6 2 The Global Routing Prefix and Subnet ID
Скачать
101 IPV6 1 Curing Address Anxiety With Compression
Скачать
103 IPV6 3 Enabling V6 Twice
Скачать
090 ACL 11 Sequence Numbers Telnet and Extended ACLs
Скачать
128 TNT 10 Cisco Password Recovery Procedures
Скачать
097 NAT 1 The Fundamentals of NAT and PAT
Скачать
109 IPV6 9 Host Discovery With NDP
Скачать
091 ACL 12 One More Telnet Test plus Absolute Time Ranges
Скачать
116 IPV6 16 Using The Link Local Address With Static Routes
Скачать
093 NTP 1 Whats Going On
Скачать
092 ACL 13 Where To Put It and Why
Скачать
104 IPV6 4 Configuring And Verifying IPV6 Addresses
Скачать
121 TNT 3 Console Logging
Скачать
086 ACL 7 Named Standard ACL Lab
Скачать
085 ACL 6 Host Any and The Order Of The Lines
Скачать
084 ACL 5 Extended ACL Lab
Скачать
083 ACL 4 Standard ACL Lab Concludes
Скачать
082 ACL 3 Standard ACL Lab Begins
Скачать
081 ACL 2 Wildcard Masks Made Easy
Скачать
080 ACL 1 Access List Rules
Скачать
079 10 Subnetting
Скачать
078 Subnet 9 Determining The Broadcast Address and Valid Address Range
Скачать
077 Subnet 8 Finding The Subnet Of An IP Address
Скачать
076 Subnet 7 Number Of Valid Hosts
Скачать
075 Subnet 6 Number Of Valid Subnets Bulldog Approach
Скачать
074 Subnet 5 Number Of Valid Subnets Classic Approach
Скачать
073 Subnet 4 Binary to Decimal Conversions
Скачать
072 Subnet 3 Decimal to Binary Conversions Dotted Decimal Example
Скачать
071 Subnet 2 Decimal to Binary Conversions Single Value Example
Скачать
070 Subnet 1 The Whys Ins and Outs of Subnetting
Скачать
069 Sec 1115 Originating A Default Route With RIP
Скачать
068 Sec 1114 Floating Static Route Lab Continues
Скачать
067 Sec 1113 Floating Static Route Lab Begins
Скачать
066 Sec 1112 Version Mismatches and Debugging Tips
Скачать
065 Sec 1111 More RIP Load Balancing Intro To Traceroute
Скачать
064 Sec 1110 Fun With RIP Load Balancing
Скачать
063 Sec 119 Administrative Distances
Скачать
062 Sec 118 Passive Interfaces
Скачать
061 Sec 117 The Cure for Autosummarization
Скачать
060 Sec 116 The Dangers of Autosummarization
Скачать
059 Sec 115 RIP Lab Concludes
Скачать
058 Sec 114 RIP Lab Continues
Скачать
057 Sec 113 RIP Lab Begins
Скачать
056 Sec 112 Split Horizon and Poison Reverse
Скачать
055 Sec 111 Intro To Distance Vector Protocols
Скачать
054 Sec 105 Default Routes Are Beautiful Sometimes
Скачать
053 Sec 104 Lab Continues Default Static Routing
Скачать
052 Sec 103 Lab Continues Host Static Routing
Скачать
051 Sec 102 Lab Continues Intro To Debug IP Packet
Скачать
050 Sec 101 Lab Topology Pings And HAS Networking
Скачать
049 Sec 92 DHCP Fundamentals
Скачать
048 Sec 91 DNS And ARP
Скачать
047 Sec 83 Multiplexing and Intro To Port Numbers
Скачать
046 Sec 82 The Comparison Continues
Скачать
045 Sec 81 TCP Good UDP Bad
Скачать
044 Sec 77 The Description and Interface Range Commands
Скачать
043 Sec 76 Slashes and Console Port Options
Скачать
042 Sec 75 Autonegotiation
Скачать
041 Sec 74 Telnet Labs End
Скачать
040 Sec 73 Telnet Labs Begin
Скачать
039 Sec 72 Creating A Non Default SVI
Скачать
038 Sec 71 Introduction To SVIs
Скачать
036 Routing 4 Connected Routes Walkthrough
Скачать
037 Routing 5 Static Route Walkthrough
Скачать
033 Routing 1 IP Addresses Subnet Masks and Binary Conversions
Скачать
035 Routing 3 The Private IP Address Classes
Скачать