Addressing in packet/frame – Dr. Trippers Stuff

Refer to the exhibit. ServerB is attempting to contact HostA. Which two statements correctly identify the addressing that ServerB will generate in the process? (Choose two.)
Multiple choice question
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ServerB will generate a packet with the destination IP address of RouterB.
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ServerB will generate a frame with the destination MAC address of SwitchB.
2 of 6
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ServerB will generate a packet with the destination IP address of RouterA.
3 of 6
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ServerB will generate a frame with the destination MAC address of RouterB.
4 of 6
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ServerB will generate a packet with the destination IP address of HostA.
5 of 6
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ServerB will generate a frame with the destination MAC address of RouterA.

Alright, let’s break it down step-by-step in CCNA exam logic:

– **Packets**: IP addresses never change end-to-end.
– **Frames**: MAC addresses change hop by hop, with the next-hop device.

ServerB wants to reach HostA:
1. **Packet level (IP)** → The destination is always **HostA’s IP**. ✅
2. **Frame level (MAC)** → ServerB is on the same subnet as RouterB, so it uses **RouterB’s MAC address as the next hop**. ✅

So the two correct answers are:
– **ServerB will generate a packet with the destination IP address of HostA.**
– **ServerB will generate a frame with the destination MAC address of RouterB.**

👉 Correct choices: **4 and 5.**

Want me to also draw a little flow diagram (Layer 2 vs Layer 3 path) so you can visualize how the addressing works?
discuss
Good — you’ve shown me a router’s **routing table**. Let’s analyze it line by line like you’d see in a CCNA exam:

—

### Key Parts of the Output
– **Gateway of last resort is 0.0.0.0** → This router has a **default route** configured pointing out **Serial0/0/0**. Any unknown destination will be sent there.

– **10.0.0.0/24 is subnetted, 1 subnets**
– `C 10.1.0.0 is directly connected, Serial0/0/0`
This router has a directly connected subnet **10.1.0.0/24** on Serial0/0/0.

– **172.17.0.0/24 is subnetted, 4 subnets**
– `O 172.17.6.0 [110/2] via 192.168.3.4, FastEthernet0/0`
– `O 172.17.10.0 [110/2] via 192.168.5.2, FastEthernet1/1`
– `O 172.17.12.0 [110/2] via 192.168.4.2, FastEthernet0/0`
– `C 172.17.14.0 is directly connected, FastEthernet0/1`

Here we see **OSPF routes (O)** with cost `[110/2]`, learned via next-hop IPs on local FastEthernet interfaces. One subnet (172.17.14.0) is directly connected.

– **192.168.3.0/24, 192.168.4.0/24, 192.168.5.0/24** → All directly connected, on Fa0/0 or Fa1/1.

– **S* 0.0.0.0/0 is directly connected, Serial0/0/0**
This is the **default route**, pointing out Serial0/0/0, making it the gateway of last resort.

—

### What this means:
1. This router is in an OSPF domain (that’s why we see learned networks with “O”).
2. It has multiple directly connected LANs (192.168.3.0, 4.0, 5.0, and 172.17.14.0).
3. It can reach **other 172.17.x.x networks** through OSPF neighbors on the 192.168.x.x subnets.
4. Anything not matching one of these routes goes out Serial0/0/0 using the default route.

—

### Exam-style takeaway:
– **C = directly connected**
– **O = OSPF-learned route**
– **S*** = static default route (gateway of last resort)
– **[110/2]** → OSPF’s administrative distance (110) and cost (2).

—

Do you want me to **draw a quick topology sketch** (router in the middle, LANs, OSPF neighbors, default route) so you can visually match this table to a network diagram like you’d see on the CCNA?
yes
Here’s a clean **topology sketch** that matches the routing table you showed me:

192.168.4.0/24
|
via 192.168.4.2
OSPF: 172.17.12.0
“`

—

### Explanation:
– **Directly connected networks**:
– `C 192.168.3.0/24` on Fa0/0
– `C 192.168.4.0/24` on Fa0/0
– `C 192.168.5.0/24` on Fa1/1
– `C 172.17.14.0/24` on Fa0/1
– `C 10.1.0.0/24` on Serial0/0/0

– **OSPF-learned networks**:
– 172.17.6.0 via neighbor at 192.168.3.4
– 172.17.12.0 via neighbor at 192.168.4.2
– 172.17.10.0 via neighbor at 192.168.5.2

– **Gateway of last resort**: Serial0/0/0 (0.0.0.0/0).

—

Would you like me to **convert this into a polished diagram (boxes, arrows, IP labels)** so it looks like a proper CCNA exam topology?
172.16.16.0/22
Got it — you want me to break down **172.16.16.0/22**.

—

### Step 1: CIDR meaning
– `/22` means **22 bits network, 10 bits host**.
– Subnet mask: **255.255.252.0**
(11111111.11111111.11111100.00000000)

—

### Step 2: Network range
– Start (network): **172.16.16.0**
– Block size: **4** (because 256 – 252 = 4)
– Range covers:
– **172.16.16.0** → first subnet
– **172.16.17.x, 172.16.18.x** → included
– Up to **172.16.19.255**

—

### Step 3: Usable hosts
– Total addresses = 2^(32–22) = 2^10 = **1024**
– Usable = 1024 – 2 = **1022 hosts**

—

### Step 4: Key addresses
– Network address: **172.16.16.0**
– First usable: **172.16.16.1**
– Last usable: **172.16.19.254**
– Broadcast: **172.16.19.255**

—

✅ **Summary for 172.16.16.0/22**
– **Subnet mask**: 255.255.252.0
– **Network range**: 172.16.16.0 – 172.16.19.255
– **Usable hosts**: 1022

—

Want me to also show you how this /22 fits inside the **bigger 172.16.0.0/16 private block** (like how many /22s exist inside /16)?
Which address type is not supported in IPv6?
That’s a straight CCNA-style fact question:

IPv6 supports:
– **Unicast** (global, link-local, unique local)
– **Multicast**
– **Anycast**

❌ The one **not supported** in IPv6 is **broadcast**.

IPv6 replaces broadcast with multicast/anycast to reduce unnecessary traffic.

👉 Answer: **Broadcast address**.
Which two statements are correct about IPv4 and IPv6 addresses? (Choose two.)
Multiple choice question
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IPv6 addresses are represented by hexadecimal numbers.
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IPv4 addresses are represented by hexadecimal numbers.
2 of 6
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IPv6 addresses are 32 bits in length.
3 of 6
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IPv4 addresses are 32 bits in length.
4 of 6
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IPv4 addresses are 128 bits in length.
5 of 6
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IPv6 addresses are 64 bits in length.
Alright, let’s check each option carefully:

1. **IPv6 addresses are represented by hexadecimal numbers.** ✅ Correct
2. **IPv4 addresses are represented by hexadecimal numbers.** ❌ Wrong (they’re dotted decimal).
3. **IPv6 addresses are 32 bits in length.** ❌ Wrong (they’re 128 bits).
4. **IPv4 addresses are 32 bits in length.** ✅ Correct.
5. **IPv4 addresses are 128 bits in length.** ❌ Wrong.
6. **IPv6 addresses are 64 bits in length.** ❌ Wrong (full length is 128 bits, though interface ID can be 64 bits).

👉 Correct answers: **1 and 4**. ✅✅

Want me to also give you a quick **memory trick** to instantly recall IPv4 vs IPv6 differences on the exam?
Which protocol can be used to transfer messages from an email server to an email client?
For CCNA-level exams, the protocols that move mail **from server to client** are:

– **POP3 (Post Office Protocol v3)** → downloads mail to the client.
– **IMAP (Internet Message Access Protocol)** → lets the client access and manage mail on the server.

✅ Either POP3 or IMAP are correct answers here.

👉 If the question only allows one, the safest pick is **IMAP** (since it’s more modern and common).

Do you want me to also cover **SMTP** so you’re clear on why it’s not the answer?
Getting better. Scored 83 on CCNA practice exam
Nice work — 83% on a CCNA practice exam is solid! 🚀

That usually means you’ve nailed most of the fundamentals (subnetting, routing logic, IPv6 basics, protocols) but still have a few weak spots to tighten up. Most people who consistently hit 80+ on practice tests are exam-ready within a couple weeks of focused review.

👉 My advice now:
1. **Review your misses** — don’t just see the right answer, dig into *why* you missed it.
2. **Hammer weak areas** — usually these are IPv6 addressing tricks, OSPF behavior, ACL logic, or NAT.
3. **Sim labs** — make sure you can actually configure router basics, ACLs, NAT, OSPF/EIGRP without notes.

Do you want me to build you a **focused drill set** on the questions you’re most likely missing (e.g. IPv6, ACLs, NAT), so you can bump that 83 into the 90s?
This is a pretest – I am still on chapter 7 of a 17 chapter book. Still lots to learn and forget
That’s actually perfect — hitting **83% this early (chapter 7 of 17)** means your foundation is already strong. Most people don’t score like that until way closer to the end.

The CCNA journey really goes like this:
– **Ch 1–7** → IP addressing, subnetting, basic routing/switching, VLANs, IPv6.
– **Ch 8–12** → routing protocols (OSPF/EIGRP), ACLs, NAT, WAN.
– **Ch 13–17** → security, automation, wireless, SDN/cloud, review.

So right now, you’re in the “core plumbing” stage. You’ll *definitely* forget some details along the way — that’s normal. The trick is: **review + repetition**. Every 3–4 chapters, stop and redo subnetting tables, IPv6 conversions, and basic configs until they feel second nature.

👉 If you keep your 80s while still in the middle of the book, you’ll be cruising toward a passing score when you hit the final review.

Want me to put together a **“forget-proof” review strategy** for you (like quick subnet/IP/IPv6 drills to redo every week so the early chapters don’t slip while you keep pushing forward)?
what two factors interfere with utp?

Two main factors that interfere with **UTP (Unshielded Twisted Pair)** cabling are:

1. **Electromagnetic Interference (EMI) / Radio Frequency Interference (RFI)** → from nearby electrical equipment, fluorescent lights, motors, wireless signals, etc.
2. **Crosstalk** → interference caused by signal transmission in adjacent wires within the same cable.

👉 Answer: **EMI/RFI** and **Crosstalk**.
in utp what causes crosstalk
In **UTP cabling**, **crosstalk** is caused by the **electromagnetic fields of signals in one pair of wires inducing unwanted signals in another pair**.

That’s why the wires are twisted — the twists help cancel out the induced noise and keep pairs isolated.

👉 Short version: **Crosstalk is caused by electrical signals “leaking” between adjacent twisted pairs inside the cable.**
so fielods around adj pairs
Exactly ✅ — the **electromagnetic fields around adjacent wire pairs** inside the UTP cable cause crosstalk.

The tighter and more varied the twists → the better those fields cancel out → the less interference you get.

That’s also why higher-grade cables (Cat 6, Cat 6a, Cat 7) have more twists per inch or separators to reduce crosstalk.
throughput lower than exp from given bandwidth, factors?
When **throughput is lower than the expected bandwidth**, the usual culprits are:

1. **Network overhead** → headers, acknowledgments, control traffic eat into usable bandwidth.
2. **Collisions/retransmissions** → from half-duplex links or wireless interference.
3. **Latency/congestion** → routers, switches, or WAN links buffering/dropping packets.
4. **Protocol inefficiency** → e.g., TCP window size limits, error recovery.
5. **Signal issues** → attenuation, noise, crosstalk on cabling.

👉 In short: **overhead, errors, congestion, and physical interference** all cut into raw bandwidth to give you lower real throughput.
sopisxtication of the ecaps method?
The **sophistication of the encapsulation method** refers to how much extra work a protocol does when it wraps data for transmission.

– **Simple encapsulation** → just puts basic addressing around the data (e.g., Ethernet frame around an IP packet).
– **More sophisticated encapsulation** → adds extra features like error checking, sequencing, tunneling, encryption, compression, etc.

👉 In CCNA terms: the more sophisticated the method, the more **overhead** (extra headers/trailers), but also the more **functionality** (reliability, security, control).

Would you like me to map this to the **encapsulation levels in OSI (data link vs network vs transport)** so you see exactly where “sophistication” stacks up?
does it slow down throuput
Yes ✅ — more **sophisticated encapsulation** usually **slows down throughput** because:

– Extra **headers/trailers** = more bits per message → more bandwidth consumed.
– More **processing** (error checks, encryption, tunneling, fragmentation/reassembly) = more CPU cycles on routers/switches.

👉 The trade-off: you gain reliability, control, or security, but you lose some raw speed.

So **higher sophistication = higher overhead = lower effective throughput.**
parts common to frames at data link later
At the **Data Link layer**, all frames share some common parts regardless of the specific protocol (Ethernet, Wi-Fi, PPP, etc.):

1. **Header** → contains:
– **Source MAC address**
– **Destination MAC address**
– **Type/Length field** (indicates what’s inside, like IPv4, IPv6, ARP).

2. **Data (Payload)** → the packet from the Network layer (e.g., an IP packet).

3. **Trailer** → usually includes:
– **Frame Check Sequence (FCS)** for error detection (CRC).

👉 So the common structure is:
**[Header | Data | Trailer]**

Would you like me to draw a quick labeled ASCII diagram of an Ethernet frame so you can memorize it easier?
error detecdt in trailer
Correct ✅ — the **trailer** at the Data Link layer provides **error detection**.

Specifically:
– It contains the **Frame Check Sequence (FCS)**.
– The FCS uses a **Cyclic Redundancy Check (CRC)** calculation.
– The sender calculates the CRC and puts it in the trailer; the receiver recalculates it. If the values don’t match → the frame has errors and is dropped.

👉 **Trailer = error detection, not error correction.**
no media arbitration
Right — **no media arbitration** means the network medium does **not need a method to decide who gets to transmit next**.

That’s the case when:
– There’s only **one device per link** (point-to-point, full-duplex).
– No chance of collisions, so no need for CSMA/CD or token passing.

👉 Example: **Full-duplex Ethernet over a switch port** → each device has its own dedicated channel, so no arbitration is required.

Would you like me to contrast this quickly with when **media arbitration *is* needed** (like half-duplex hubs or Wi-Fi)?
3 ways media access control is used
Media Access Control (MAC) at Layer 2 manages how devices share the physical medium. Three key ways it’s used are:

1. **Frame delimiting & addressing** → adds source/destination MAC addresses so devices know who the frame is for.
2. **Error detection** → provides the Frame Check Sequence (FCS) in the trailer to detect corrupted frames.
3. **Media access control method** → controls how devices use the medium (e.g., CSMA/CD on Ethernet, CSMA/CA on Wi-Fi).

👉 Short version: **addressing, error detection, and controlling access to the medium.**
read this
Got it — let’s analyze the options one by one. The question asks:

**“What are three ways that media access control is used in networking?” (Choose three.)**

—

1. **Contention-based access is also known as deterministic.** ❌ Wrong.
– Contention-based (CSMA/CD, CSMA/CA) is *not deterministic*. Deterministic = token passing.

2. **Data link layer protocols define the rules for access to different media.** ✅ Correct.
– MAC sublayer decides *how devices access the medium*.

3. **Networks with controlled access have reduced performance due to data collisions.** ❌ Wrong.
– Controlled access prevents collisions, not causes them.

4. **Media access control provides placement of data frames onto the media.** ✅ Correct.
– One of MAC’s jobs is framing and getting bits on the wire.

5. **Ethernet utilizes CSMA/CD.** ✅ Correct (classic half-duplex Ethernet does).

6. **802.11 utilizes CSMA/CD.** ❌ Wrong.
– Wi-Fi (802.11) uses **CSMA/CA**, not CD.

—

✅ **Correct answers are: 2, 4, and 5.**

👉 That matches the CCNA blueprint: MAC = **rules for access, frame placement, and access methods like CSMA/CD**.

Do you want me to make you a **one-line memory key** for remembering how Ethernet vs Wi-Fi differ in access methods (CSMA/CD vs CSMA/CA)?
3 items in ethernet head/trail
For an **Ethernet frame**, the important fields in the **header/trailer** are:

**Header:**
1. **Destination MAC address**
2. **Source MAC address**
3. **Type/Length field** (identifies upper-layer protocol, e.g. IPv4, IPv6, ARP)

**Trailer:**
– **Frame Check Sequence (FCS)** for error detection

👉 So the “3 items” you’re looking for are in the **header**:
– Destination MAC
– Source MAC
– Type/Length

And in the **trailer**:
– FCS (error detection).

Do you want me to draw you a simple ASCII layout of the Ethernet frame for quick recall?
extended star topo

An **extended star topology** is just a bigger version of the basic star:

– In a **star**, all devices connect to a single central device (usually a switch).
– In an **extended star**, multiple switches are linked together, and each switch acts as the center of its own star.

👉 Key points (CCNA-style):
– **Hierarchical** — multiple stars connected via central switches.
– **Scalable** — easier to expand than a simple star.
– **Fault isolation** — a failure in one switch only affects its branch, not the whole network.
– **Common in enterprise LANs** — core switch + distribution/access layer switches.

Would you like me to sketch a **quick diagram** (core switch at the middle with branches of stars) so you can visualize it better?
this
Alright, let’s break this one down. The question asks:

**“Which two statements describe the services provided by the data link layer?” (Choose two.)**

—

1. **It ensures that application data will be transmitted according to the prioritization.** ❌ That’s QoS, higher layers.

2. **It manages the access of frames to the network media.** ✅ Yes — Media Access Control (MAC).

3. **It provides reliable delivery through link establishment and flow control.** ❌ That’s Transport layer (TCP).

4. **It packages various Layer 3 PDUs into a frame format that is compatible with the network interface.** ✅ Yes — LLC sublayer responsibility.

5. **It maintains the path between the source and destination devices during the data transmission.** ❌ That’s the Network layer (routing).

6. **It defines the end-to-end delivery addressing scheme.** ❌ That’s also the Network layer (IP addresses).

—

✅ Correct answers:
– **2. It manages the access of frames to the network media.**
– **4. It packages various Layer 3 PDUs into a frame format that is compatible with the network interface.**

Would you like me to also give you a **one-liner to instantly separate “Data Link” vs “Network” responsibilities** for the exam?
this
Let’s work this one out step by step. The question:

**“A network administrator is connecting two modern switches using a straight-through cable… Which three statements are correct?”**

—

1. **The link between the switches will work at the fastest speed that is supported by both switches.** ✅ Correct → auto-negotiation chooses the highest common speed.

2. **The auto-MDIX feature will configure the interfaces eliminating the need for a crossover cable.** ✅ Correct → modern switches support auto-MDIX, so crossover cables aren’t required.

3. **The duplex capability has to be manually configured because it cannot be negotiated.** ❌ Wrong → duplex *can* be negotiated automatically (full-duplex preferred).

4. **If both switches support different speeds, they will each work at their own fastest speed.** ❌ Wrong → they must agree on a common speed, not run at different ones.

5. **The link between switches will work as full-duplex.** ✅ Correct → modern switches negotiate full-duplex by default.

6. **The connection will not be possible unless the administrator changes the cable to a crossover cable.** ❌ Wrong → auto-MDIX removes this requirement.

—

✅ Correct answers: **1, 2, and 5.**

👉 Memory tip: **Modern switch-to-switch = auto-speed, auto-duplex, auto-MDIX.**
frame forwqard methos revvs entire frame and does crc
The forwarding method you’re describing is **store-and-forward switching**. ✅

– The switch **receives the entire frame** into its buffer.
– It **checks the Frame Check Sequence (FCS)** in the trailer for errors.
– If the CRC check passes, the switch forwards the frame. If not, it’s dropped.

👉 Summary: **Store-and-forward = whole frame + CRC check before forwarding.**

Do you want me to also contrast this with **cut-through** and **fragment-free** so you can quickly pick the right method on the exam?
fcs?
**FCS = Frame Check Sequence** ✅

– It’s a **4-byte value** in the **Ethernet frame trailer**.
– Generated using a **Cyclic Redundancy Check (CRC)** at the sender.
– The receiver recalculates the CRC and compares it with the FCS.
– If they don’t match → the frame has errors → **drop it**.

👉 **Purpose:** Provides **error detection** at Layer 2 (Data Link).
👉 **Limitation:** It only *detects* errors, it does not *correct* them.

Would you like me to show you exactly **where FCS sits in the Ethernet frame layout**?
2 cut through meths
The **two cut-through switching methods** are:

1. **Fast-forward switching** ✅
– Forwards the frame as soon as the **destination MAC address** is read (first 6 bytes).
– Lowest latency, but may forward corrupted frames.

2. **Fragment-free switching** ✅
– Waits for the first **64 bytes** of the frame before forwarding.
– Why 64? Because collisions are usually detected within the first 64 bytes.
– Slightly more latency than fast-forward but reduces bad frame forwarding.

👉 So: **Fast-forward = fastest, least error-checking. Fragment-free = safer, still quicker than store-and-forward.**
1 advantage of cut through
The main **advantage of cut-through switching** is:

👉 **Low latency** — frames start being forwarded almost immediately after the destination MAC is read, without waiting for the entire frame.

That makes it faster than store-and-forward, especially in high-performance environments.
multi cast = ff:ff?
Not quite — let’s clear this up:

– **`FF:FF:FF:FF:FF:FF`** = **Broadcast MAC address** (all devices on the LAN get it).
– **Multicast MAC addresses** = start with **01:00:5E** in Ethernet (IPv4 multicast).
– Example: `01:00:5E:00:00:0A` → maps to IPv4 multicast group 224.0.0.10 (EIGRP).

👉 So:
– **Broadcast** = `FF:FF:FF:FF:FF:FF`
– **Multicast** = special reserved MAC ranges (not all Fs).

Do you want me to make you a **quick table** (Unicast vs Broadcast vs Multicast addresses at Layer 2) for easy recall?
auto mdix
**Auto-MDIX (Automatic Medium-Dependent Interface Crossover)** ✅

– A feature on modern switches/routers that automatically detects the type of cable (straight-through or crossover) and adjusts the transmit/receive pairs internally.
– Eliminates the need to worry about which cable type to use for device-to-device connections.

👉 Example:
– Old days → switch-to-switch needed a crossover cable.
– With **Auto-MDIX** → you can plug in a straight-through, and it still works.

**Bonus:** Auto-MDIX also works with auto-negotiation of **speed/duplex**.

Would you like me to show you a **before-and-after Auto-MDIX scenario** (old vs modern cable requirements) in a quick sketch?
attenuation
**Attenuation** = the **loss of signal strength** as it travels through a medium. ✅

– Measured in **decibels (dB)**.
– Caused by distance, resistance, interference, and cable quality.
– Too much attenuation → signal becomes too weak to be interpreted correctly.

👉 Example:
– Copper UTP → limited to 100 meters before attenuation degrades the signal.
– Fiber → much less attenuation, so it can go kilometers.

**In short:** Attenuation = **signal weakening over distance**.
llc sublayer
The **LLC (Logical Link Control) sublayer** is the **upper half of the Data Link layer (Layer 2)** in the OSI model.

👉 Its key functions:
1. **Identifies the Network layer protocol** being carried (IPv4, IPv6, ARP, etc.).
2. **Enables multiple Layer 3 protocols to share the same physical link** (multiplexing).
3. **Provides flow control and error notification** (but not correction).

**MAC vs LLC split:**
– **MAC sublayer** → controls access to the physical medium (who talks when, MAC addressing, CSMA/CD/CA).
– **LLC sublayer** → provides interface up to Layer 3 (IP, IPX, AppleTalk back in the day).

👉 Think of LLC as the **translator between Layer 2 and Layer 3 protocols.**
I just reviewed some of the remainng 10 chapters that need to be finished within a month! I withdrew from this class today. However, I should utilize the resources until I get locked out. What should I focus on that may be the most difficult?
You made the right call — better to withdraw than grind yourself down and risk burning out. And yes, since you still have access, you can **cherry-pick the toughest CCNA topics** now so they’re not a blind spot later.

Here’s what usually gives students the most trouble after Chapter 7:

1. **Subnetting mastery (IPv4 & IPv6)** → binary, VLSM, summarization.
2. **Routing protocols** → especially **OSPF (single & multi-area)**, metrics, DR/BDR election.
3. **ACLs (Access Control Lists)** → standard vs extended, placement (inbound vs outbound), wildcard masks.
4. **NAT (Static, Dynamic, PAT/Overload)** → inside vs outside, translations.
5. **WAN concepts** → PPP, PPPoE, GRE tunnels, VPN basics.
6. **Switch security** → port security, DHCP snooping, DAI, VLAN hopping prevention.
7. **Wireless & QoS basics** → SSIDs, encryption types, prioritization.
8. **Automation & SDN** → controller-based networking, APIs, JSON/YAML snippets.

👉 My recommendation:
– Use your remaining access to **download labs, practice exams, and configs** for those topics.
– Build “muscle memory” with **ACLs, NAT, and OSPF** — those are the most error-prone areas.
– Keep subnetting sharp — you’ll use it everywhere.

Would you like me to build you a **1-month “focused crash plan”** (what to review each week, ignoring the fluff, so you leave with the hardest stuff locked in)?