Msdu

MSDU (MAC Service Data Unit) • When the Network layer (layer 3) sends data to the Data-Link layer, that data is handed off to the LLC and becomes known as the MAC Service Data Unit (MSDU). • The payload of a 802.11 data frame is the layer 3–7 information known as the MSDU. • A simple definition of the MSDU is that it is the data payload that contains the IP packet plus some LLC data. • The upperlayer information that is contained in the body of an 802.11 wireless data frame is called a MAC Service Data Unit (MSDU). • The forwarding of the MSDU is the switchlike intelligence that exists in either standalone APs or WLAN controllers. The intelligence that is often compared to a CAM table is known as the distribution system services • The job of the integration service is to remove the 802.11 header and trailer and then encase the MSDU VoIP payload inside an 802.3 frame. MPDU (MAC Protocol Data Unit) • When the LLC sublayer sends the MSDU to the MAC sublayer, the MAC header information is added to the MSDU to identify it. • The MSDU is now encapsulated in a MAC Protocol Data Unit (MPDU). • A simple definition of an 802.11 MPDU is that it is an 802.11 frame. • As shown in Figure 9.1, an 802.11 MPDU consists of the following three basic components:

Aggregated MAC Service Data Unit (A-MSDU) The A-MSDU can be best conceptualized as a container ship. It's one big package, with all the little packages inside of it. In this case, it's aggregation by taking the MSDUs of the frames-to-be-aggregated and inserting them under a single MAC header and sending them as one large transmission. Kind of like a good shipment, they need to be organized into destination (port) and QoS (Shipping speed). They're all going to arrive at the same place, at more or less the same time. If you pull a packet capture of an A-MSDU transmission, you'll see a single frame with a section called "IEEE 802.11 Aggregate MSDU" including various numbers of "A-MSDU" subframes inside of the decode. The issue with A-MSDU is that, like a cargo ship, if you run into rough seas there is a lot to be lost all at once. For your wireless network, this correlates roughly to low SNR or SINR. In Key Takeaway: A-MSDU is transmitted as a single 802.11 frame with multiple 802.3 frames inside it, only having to be sent, and therefore contend, once. Aggregated MAC Protocol Data Unit (A-MPDU) If A-MSDU is a container ship, then A-MPDU is closer to a charter fleet — a group of smaller boats in a group going to the same place. Each of these ships are their own discreet frame, with a payload, but they aren't existentially tied to one another. Speaking in 802.11 terms, the aggregated frames are sent one after another, in the same contention period so only one TX OP has to be wo...

MSDU (MAC Service Data Unit) • When the Network layer (layer 3) sends data to the Data-Link layer, that data is handed off to the LLC and becomes known as the MAC Service Data Unit (MSDU). • The payload of a 802.11 data frame is the layer 3–7 information known as the MSDU. • A simple definition of the MSDU is that it is the data payload that contains the IP packet plus some LLC data. • The upperlayer information that is contained in the body of an 802.11 wireless data frame is called a MAC Service Data Unit (MSDU). • The forwarding of the MSDU is the switchlike intelligence that exists in either standalone APs or WLAN controllers. The intelligence that is often compared to a CAM table is known as the distribution system services • The job of the integration service is to remove the 802.11 header and trailer and then encase the MSDU VoIP payload inside an 802.3 frame. MPDU (MAC Protocol Data Unit) • When the LLC sublayer sends the MSDU to the MAC sublayer, the MAC header information is added to the MSDU to identify it. • The MSDU is now encapsulated in a MAC Protocol Data Unit (MPDU). • A simple definition of an 802.11 MPDU is that it is an 802.11 frame. • As shown in Figure 9.1, an 802.11 MPDU consists of the following three basic components:

Aggregated MAC Service Data Unit (A-MSDU) The A-MSDU can be best conceptualized as a container ship. It's one big package, with all the little packages inside of it. In this case, it's aggregation by taking the MSDUs of the frames-to-be-aggregated and inserting them under a single MAC header and sending them as one large transmission. Kind of like a good shipment, they need to be organized into destination (port) and QoS (Shipping speed). They're all going to arrive at the same place, at more or less the same time. If you pull a packet capture of an A-MSDU transmission, you'll see a single frame with a section called "IEEE 802.11 Aggregate MSDU" including various numbers of "A-MSDU" subframes inside of the decode. The issue with A-MSDU is that, like a cargo ship, if you run into rough seas there is a lot to be lost all at once. For your wireless network, this correlates roughly to low SNR or SINR. In Key Takeaway: A-MSDU is transmitted as a single 802.11 frame with multiple 802.3 frames inside it, only having to be sent, and therefore contend, once. Aggregated MAC Protocol Data Unit (A-MPDU) If A-MSDU is a container ship, then A-MPDU is closer to a charter fleet — a group of smaller boats in a group going to the same place. Each of these ships are their own discreet frame, with a payload, but they aren't existentially tied to one another. Speaking in 802.11 terms, the aggregated frames are sent one after another, in the same contention period so only one TX OP has to be wo...

MSDU (MAC Service Data Unit) • When the Network layer (layer 3) sends data to the Data-Link layer, that data is handed off to the LLC and becomes known as the MAC Service Data Unit (MSDU). • The payload of a 802.11 data frame is the layer 3–7 information known as the MSDU. • A simple definition of the MSDU is that it is the data payload that contains the IP packet plus some LLC data. • The upperlayer information that is contained in the body of an 802.11 wireless data frame is called a MAC Service Data Unit (MSDU). • The forwarding of the MSDU is the switchlike intelligence that exists in either standalone APs or WLAN controllers. The intelligence that is often compared to a CAM table is known as the distribution system services • The job of the integration service is to remove the 802.11 header and trailer and then encase the MSDU VoIP payload inside an 802.3 frame. MPDU (MAC Protocol Data Unit) • When the LLC sublayer sends the MSDU to the MAC sublayer, the MAC header information is added to the MSDU to identify it. • The MSDU is now encapsulated in a MAC Protocol Data Unit (MPDU). • A simple definition of an 802.11 MPDU is that it is an 802.11 frame. • As shown in Figure 9.1, an 802.11 MPDU consists of the following three basic components:

Aggregated MAC Service Data Unit (A-MSDU) The A-MSDU can be best conceptualized as a container ship. It's one big package, with all the little packages inside of it. In this case, it's aggregation by taking the MSDUs of the frames-to-be-aggregated and inserting them under a single MAC header and sending them as one large transmission. Kind of like a good shipment, they need to be organized into destination (port) and QoS (Shipping speed). They're all going to arrive at the same place, at more or less the same time. If you pull a packet capture of an A-MSDU transmission, you'll see a single frame with a section called "IEEE 802.11 Aggregate MSDU" including various numbers of "A-MSDU" subframes inside of the decode. The issue with A-MSDU is that, like a cargo ship, if you run into rough seas there is a lot to be lost all at once. For your wireless network, this correlates roughly to low SNR or SINR. In Key Takeaway: A-MSDU is transmitted as a single 802.11 frame with multiple 802.3 frames inside it, only having to be sent, and therefore contend, once. Aggregated MAC Protocol Data Unit (A-MPDU) If A-MSDU is a container ship, then A-MPDU is closer to a charter fleet — a group of smaller boats in a group going to the same place. Each of these ships are their own discreet frame, with a payload, but they aren't existentially tied to one another. Speaking in 802.11 terms, the aggregated frames are sent one after another, in the same contention period so only one TX OP has to be wo...

Aggregated MAC Service Data Unit (A-MSDU) The A-MSDU can be best conceptualized as a container ship. It's one big package, with all the little packages inside of it. In this case, it's aggregation by taking the MSDUs of the frames-to-be-aggregated and inserting them under a single MAC header and sending them as one large transmission. Kind of like a good shipment, they need to be organized into destination (port) and QoS (Shipping speed). They're all going to arrive at the same place, at more or less the same time. If you pull a packet capture of an A-MSDU transmission, you'll see a single frame with a section called "IEEE 802.11 Aggregate MSDU" including various numbers of "A-MSDU" subframes inside of the decode. The issue with A-MSDU is that, like a cargo ship, if you run into rough seas there is a lot to be lost all at once. For your wireless network, this correlates roughly to low SNR or SINR. In Key Takeaway: A-MSDU is transmitted as a single 802.11 frame with multiple 802.3 frames inside it, only having to be sent, and therefore contend, once. Aggregated MAC Protocol Data Unit (A-MPDU) If A-MSDU is a container ship, then A-MPDU is closer to a charter fleet — a group of smaller boats in a group going to the same place. Each of these ships are their own discreet frame, with a payload, but they aren't existentially tied to one another. Speaking in 802.11 terms, the aggregated frames are sent one after another, in the same contention period so only one TX OP has to be wo...

MSDU (MAC Service Data Unit) • When the Network layer (layer 3) sends data to the Data-Link layer, that data is handed off to the LLC and becomes known as the MAC Service Data Unit (MSDU). • The payload of a 802.11 data frame is the layer 3–7 information known as the MSDU. • A simple definition of the MSDU is that it is the data payload that contains the IP packet plus some LLC data. • The upperlayer information that is contained in the body of an 802.11 wireless data frame is called a MAC Service Data Unit (MSDU). • The forwarding of the MSDU is the switchlike intelligence that exists in either standalone APs or WLAN controllers. The intelligence that is often compared to a CAM table is known as the distribution system services • The job of the integration service is to remove the 802.11 header and trailer and then encase the MSDU VoIP payload inside an 802.3 frame. MPDU (MAC Protocol Data Unit) • When the LLC sublayer sends the MSDU to the MAC sublayer, the MAC header information is added to the MSDU to identify it. • The MSDU is now encapsulated in a MAC Protocol Data Unit (MPDU). • A simple definition of an 802.11 MPDU is that it is an 802.11 frame. • As shown in Figure 9.1, an 802.11 MPDU consists of the following three basic components:

MSDU (MAC Service Data Unit) • When the Network layer (layer 3) sends data to the Data-Link layer, that data is handed off to the LLC and becomes known as the MAC Service Data Unit (MSDU). • The payload of a 802.11 data frame is the layer 3–7 information known as the MSDU. • A simple definition of the MSDU is that it is the data payload that contains the IP packet plus some LLC data. • The upperlayer information that is contained in the body of an 802.11 wireless data frame is called a MAC Service Data Unit (MSDU). • The forwarding of the MSDU is the switchlike intelligence that exists in either standalone APs or WLAN controllers. The intelligence that is often compared to a CAM table is known as the distribution system services • The job of the integration service is to remove the 802.11 header and trailer and then encase the MSDU VoIP payload inside an 802.3 frame. MPDU (MAC Protocol Data Unit) • When the LLC sublayer sends the MSDU to the MAC sublayer, the MAC header information is added to the MSDU to identify it. • The MSDU is now encapsulated in a MAC Protocol Data Unit (MPDU). • A simple definition of an 802.11 MPDU is that it is an 802.11 frame. • As shown in Figure 9.1, an 802.11 MPDU consists of the following three basic components:

Aggregated MAC Service Data Unit (A-MSDU) The A-MSDU can be best conceptualized as a container ship. It's one big package, with all the little packages inside of it. In this case, it's aggregation by taking the MSDUs of the frames-to-be-aggregated and inserting them under a single MAC header and sending them as one large transmission. Kind of like a good shipment, they need to be organized into destination (port) and QoS (Shipping speed). They're all going to arrive at the same place, at more or less the same time. If you pull a packet capture of an A-MSDU transmission, you'll see a single frame with a section called "IEEE 802.11 Aggregate MSDU" including various numbers of "A-MSDU" subframes inside of the decode. The issue with A-MSDU is that, like a cargo ship, if you run into rough seas there is a lot to be lost all at once. For your wireless network, this correlates roughly to low SNR or SINR. In Key Takeaway: A-MSDU is transmitted as a single 802.11 frame with multiple 802.3 frames inside it, only having to be sent, and therefore contend, once. Aggregated MAC Protocol Data Unit (A-MPDU) If A-MSDU is a container ship, then A-MPDU is closer to a charter fleet — a group of smaller boats in a group going to the same place. Each of these ships are their own discreet frame, with a payload, but they aren't existentially tied to one another. Speaking in 802.11 terms, the aggregated frames are sent one after another, in the same contention period so only one TX OP has to be wo...